Materials for the Study of Variation Treated with Especial Regard to Discontinuity in the Origin of Species

Man having 3 phalanges in the thumb of the left hand together with a supernumerary digit. (Fig. 89.) This case in several respects resembles the left hand of the subject described by WINDLE. Th«- four ringers were normal. The thumb stood in its normal relations to them, but was finger-like in form, having three phalanges in addition to the metacarpal. On the radial side of Bones of left hand of No. 486, shewing Condition III. (After RIJKEBUSCH.) this 3-phalan_ned digit there was a supernumerary digit, having two phalanges and a separate metacarpal, which articulated with

tin' head of the metacarpal of the thumb .and the trapezium. In the carpus of this hand there was a supernumerary bone which is described as an n\ I'i'/ifni/i'. The bones and muscles of this limb are described in detail. The thumb and the supernumerary digit were closely webbed together and were very slightly moveable. Specimen first described by RUKEBUSCH, Bijdr. tot de Kennis der Polydactylie, Utrecht, 1887, Plates, and subsequently by SPRONCK, Arch, nderl., xxn. 1888, p. 235, PL vi.— ix. [Condition III.]

*487. Woman having 6 digits on each hand and foot as follows. In each hand the thumb has three phalanges, and internal to it articulating with the same metacarpal is an extra digit having two phalanges [measurements given] webbed to the three -phalanged thumb. [Condition III of the manus.] Right foot has six complete metatarsals and digits very regularly set, one of them being internal to but longer than the hallux which has two phalanges as usual. The digit internal to it has also two phalanges. Left foot has also an extra digit with two phalanges longer than the hallux, placed internal to and articulating with the rnetatarsal of the hallux which has two phalanges as usual. Many members of family polydactyle [particulars given]. STRUTHERS, Edin. New Phil. Jour., 1863 (2), p. 93. [Note in this case that in the feet the digits added internally to hallux are greater than it, and they thus stand as the largest terms in the series, the other members being Successive to them. The series thus does not decline from the hallux both internally and externally in the way seen in most other cases of extra digits on the internal side of the limb.]

Man having six digits, each with three phalanges, on each hand. FIG. 90. Bones of right hand of No. 488 shewing Condition IV. n1 and «2 represent the scaphoid. In, lunar, c, cuneiform, tm, trapezium. til, trapezoid. m, magnum, u, unciform. etc1, ac2 are supernumerary bones. The digits were arranged in two groups, which were to some extent opposable to each other. The digits II, III, IV and V stood in their n»nnai positions and were properly formed. In the place where the thumb should stand there were two digits, each with three phalange-;. Of these tinexternal (d2) was of about the length and form of the index finger while the internal, d1, was a good deal short"!- and more slender. The bones of the carpus are shewn in Kig. svv The scaphoid was represented in the right hand by two bones nl and ir, and there were two accessory bones, acl and ac2 placed in the posit i« ins shewn. The two hands were almost exactly alike, save for slight differences in the carpal bones [see original figures], and fur the fact that in the left hand the internal of the two digits of the radial group was rather more rudimentary. RUDINGER, Belt)-. :nr Anat. des Gehororgans, d. venosen Bluibahnen il. Si'lii'iilfllinlile, sowie der uberzahligen Finger, Miinchen, 1876, Plate. [Both hands in Condition IV.]

4s9. A female child born to the last case, No. 488, had the right hand in the same condition as that of the father, while the left hand differed from it in the presence of an additional rudimentary finger arising from the ulnar side of the digit d*. This additional finger bore a nail but it appeared to consist of two joints only and to be attached to the metacarpus by ligamentary connexions. Ri'DiNOKK, ibid. [Right hand in Condition IV; left hand departing from the Conditions enumerated. Compare with maims of Cat, Fig. 84.]

*490. .Man. Riyht liaiid bore six digits and metacarpals. The most external digit was a normal minimus, succeeded by digits IV and III webbed together. Next to III there was an index. Internal to this and separated from it by a small metacarpal space was a 3-phalanged long digit much as in Windle's case, No. 481, and internal to it is a 2-phalanged thumb of nearly normal form like that of No. 485. Left hand bore seven digits but six metacarpals. .Minimus normal. IV, III and II webbed together. Internal to II was a U-phalanged digit much as in the right hand; but internal to this there was a metacarpal bearing two digits, an external having .'} phalanges and an internal having 2 phalanges. Each foot had six digits and six metatarsals (q.v.). Redescribed from the account and figures given by GRUBKK, Hull. Ac. Sci. Pet., xvr. 1*71, ]>. .S")0, jiff*. [Right hand Condition IV, left hand Condition V.]

401. Chilil ImviiiL' six lingers on each hand. The fingers were uniU'd together. In the thumb [?both] there were three phalanges and the length of the thumb was as great as that of the "other fingers." Dnsois, Arch. gen6r. </<• M>',l., 1826, Ann. iv. T. xi. ji. 1 is ; this case is quoted by GKOFFROY Sx HILAIRK, lli*t. </.•.-• Anom., i. p. '227 Note. [?Con.litiun IV.] B1. Digits in two homologous groups, forming " Double-hands." *492. DOUBLE-HAND I. Seven digits in two groups of four and three. Male: left arm abnormal, having seven digits arranged in two groups, the one an external group of four normal digits, and the other an internal group of three digits2. (Fig. 91.) Described from a dried specimen in Mus. of Harvard Med. School. The man was a machinist and found the hand not merely very useful to him in his business, but he also thought that it gave him advantages in playing the piano.

" The fore-arm consists of the normal left ulna and of a right one in the place of a radius. The left one shews little that calls for comment, excepting that there is a projection outward at the place of the lesser sigmoid cavity to join a corresponding projection from the other ulna. The upper surface of this projection articulates with the humerus. At the lower end the styloid process is less prominent than usual, and the head rather broad. The right or extra ulna is put on hind side before, that is, the back of the olecranon projects forward over the front and outer aspect of the humerus. If the reader will place his right fore-arm on the outer side of the left one he will see that it is necessary for the

FIG. 91. I. The left hand of No. 492 from the dorsal surface. II. The humerus and two bones of the fore-arm at the elbow of the same case. 0, olecranon. O2, the secondary "olecranon". I, the inner condyle of the humerus. I2, the second or external " inner condyle." ulna to be thus inverted if the thumbs are to touch and the palms to be continuous. This olecranon is thinner, flatter, and longer than normal. The coronoid process is rudimentary. From the side of this process and from the shaft just behind it arises the projection already

2 This is the case reported by Jackson, to Bost. Soc. of Mfd. Imp., 18.VJ. referred to which meets a similar one from the normal ulna [Fig. 89, II]. < )n the front of this there is a small articular surface looking forward which su'_rLTests ;i part of the convexity of the head of the radius. The ii|>]"T .-irt icular surface shews a fissure separating it from the side of i In- olecranoii which is not found in the normal ulna. These projections which touch each other are held together by a strong interosseous ligament. Th«- lower end of this ulna is very like the other, only somewhat broader. The mode of union of the lower ends could not be seen without unwarrantable injury to the specimen. There can hardly have been any definite movement between these bones. Perhaps the ligaments may have permitted some irregular sliding, but it is impossible to know. These bones have been described first because their nature is very clear and, once understood, is a key to the more difficult interpretation of the lower end of the humerus."

The upper end of the humerus presented nothing noteworthy. A detailed description and figures are given, from which it appears that the lower end of the humerus had such a form as might be produced liy >awing off the greater part of the external condyle and applying in place of it the internal condyle of a riyht humerus. The carpus seen from the dorsal side had the structure shewn in the diagram (Fig. 92). The proximal row consisted of three bones besides the two pisiforms (pl and jr). There was a cuneiform at either side of the wrist, and between them a bone evidently composed of a pair of semilunars, having a slight notch in its upper border. At each end of

Fi«. (,»2. Diagram of the carpal bones iu the left hand of No. 492 from the dorsal surface. pi.<1. <•)/', i/1, 7/i1, pisiform, cuneiform, unciform and magnum of the external or normal half of the hand consisting of four fingers ; pis'2, cu-, u-, m~, the similar bones for the internal group of three fingers. lul+", the compounded lunar elements corresponding to the two groups, j, bone placed as trapezoid. the second row is an unciform bearing the middle and ring fingers. Next came two ossa niagna very symmetrically placed, each bearing the metacarpal of a medius. Between these is a bone which DWIGHT states

to have clearly represented the trapezoicl of the left hand, bearing an index finger. The metacarpals and phalanges needed no description. The muscles are described in detail [?.«.]. Some of the, features in the distribution of the arteries and nerves are of interest, and I transcribe Dwight's account in full. It appears that, like the bones, the vessels and nerves proper to the radial side of a normal left arm have in a measure been transformed into parts proper to the ulnar side of a right arm.

"TiiE ARTERIES. The brachial divides at about the junction of the middle and lower thirds of the humerus. The main continuation, which is the ulnar proper, runs deeply under the band thought to represent the pronator radii teres, to the deep part of the fore-arm where it gives off the interosseous. Above the elbow there is a branch running backward between the internal condyle and the olecranon. The interosseous branches are not easy to trace. There seems to be an anterior interosseous and three branches on the back of the forearm, one running on the membrane and one along each bone. At least two of them share in a network on the back of the carpus. Having reached the hand the ulnar artery runs obliquely across the palm to the cleft between the two sets of fingers, supplying the four normal fingers and the nearer side of the extra middle finger. The other branch of the brachial crosses the median nerve and runs, apparently superficially, to the outer side of the fore-arm. It supplies the little and ring fingers and the corresponding side of the middle finger of the supernumerary set. There is no anastomosis in the palm between the superficial branches of the two arteries. Each gives off a deep branch at the usual place, which forms a deep palmar arch from which some interosseous arteries spring. There is also an arterial network over the front of the carpal bones. The arteries of the deep parts of the hand cannot all be seen.

THE NERVES. The ulnar nerve proper pursues a normal course and supplies the palmar aspect of the little finger and half the ring finger of the normal hand. Near the wrist it gives off a very small posterior branch, which is not well preserved, but which seems to have had less than the usual distribution. The median nerve is normal as far as the elbow, running to the inner side of the extra condyle. It is then lost in the dried fibers of the flexor sublimis, from which it emerges in two main divisions near the middle of the fore-arm. The inner of these soon divides into two, of which one supplies the adjacent sides of the ring and middle fingers and the other those of the middle and index fingers of the normal hand. The outer division of the median supplies the outer side of the index and both sides of the extra middle finger and one side of the extra ring finger. One of the branches to the index gives off a dorsal branch, and there is a doubtful one for the extra middle finger. The musculo-spiral nerve passes behind the humerus as usual. A nerve which is undoubtedly continuous with it emerges from the hardened muscles over the fused outer condyles. It seems to be the radial branch changed into an ulnar. It runs with the extra ulnar artery to the hand and sending a deep branch into the palm, goes to the ring finger. There is a detached branch on the other side of the little finger which in all probability came from it. The deep branch sends a twig along the metacarpal bone of the ring finger. It probably

supplied the side of tinrim; timber left unprovided for, but this is uncertain. Assuming this t<> h;i\e been the case, each ulnar nerve supplies the palmar surface of one linger and a lialf, the median supplviiiLC tinremaining lingers of t)oth hands. Unfortunately no dorsal Kranehes except tliu.se mentioned have been preserved." [This is a case of high significance. We shall come back tn it lu-ivat'tiT. Meanwhile it will be noted that in it we meet again the old dittiruliy so often presented by cases of Meristic Variation. In this fore-arm there is already one true ulna. Internal to it is another bone also formed as an ulna. We may therefore, indeed we must, call it an ulna. But is it an "ulna"? To answer this we must, first answer the question what is an ulna? Similarly, is the second pisiform a "pisiform," or is the second ulnar nerve an " ulnar " nerve ? These questions force themselves on the mind of anyone who tries to apply the language of orthodox morphology to this case, but to them there is still no answer. Or, rather, the answer is given that an " ulna," a " pisiform " and the like are terms that have no fixed, ideal meaning, symbols of an order that we have set up but which the body does not obey. An " ulna" is a bone that has the form of an ulna, and a " pisiform " is that which has the form of a pisiform. [f we 1 1 y to pass behind this, to seek an inner and faster meaning for these conceptions of the mind, we are attempting that for which Nature ^ives no warrant : we are casting off from the phenomenal, from the things which appear, and we set forth into the waste of metaphysic.]

493. P'".v ha\ing abnormalities in the left hand as follows. The four outer lingers II — V are normal in form and proportions. Internal to these is firstly an opposable digit with a single metacarpus and single proximal phalanx but having two distal phalanges side by side webbed together. Internal to this partially double thumb are two digits in series, each with a metacarpal and three phalanges, respectively re- >emliling the annularis and minimus of a /•!;///(, hand. SxRUTlIERS, Edin. New /'////. ,/<>iir., 186-'} (2), p. 90, PI. n. fig. 5. [Not representing any uf t IK- Conditions.]

41)4. Male infant, one year and live months, examined alive, having the right hand abnormal, possessing seven digits, arranged in two groups, an ulnar group of four and a radial group of three. Each digit had three phalanges, but the ring and middle lingers of the ulnar group are webbed in the region of the proximal phalanges. The ulnar group seemed to articulate with the carpus in the usual uay. The radial group probably formed joints with more thau one facet on the trapezium, and possibly also with a surface on the lower end of the radius. It did not seem that the carpal bones were increased in number, for the right wrist had the same circumferential measurement as the left, which was normal. The lower end of the ulna did not seem to articulate normally with the carpus. The elbow was also abnormal, and it seemed "as if the ulna were dislocated inwards." BALLAXTYNK, .1. W., ;.,//;;. .I/,-/. Jour., 1893, CDLI. p. 623, Jig. [Possibly this condition approached to that found in the last cases.]

495. DOUBLE-HAND II. Eight digits in two groups of four and four. Woman (examined alive) having eight fingers in the left hand arranged as follows (Fig. 93). With the exception of the left arm the body was normal. The limb was very muscular. The shoulderjoint was natural. The external condyloid ridge of the hunx-rus was strongly defined. The muscles and tendons of the fore-arm were so prominent that it was not easy to decide whether there was a second radius or ulna, but Murray eventually came to the

conclusion that there was no such extra bone. The fore-arm could be only partially flexed. The eight fingers were arranged in two groups of four in each, one of the groups standing as the four normal fingers do, and the other four being articulated where the thumb should be. There was no thumb distinguishable as such, but it is stated that there was a protuberance on the dorsal side of the hand, between the two groups of fingers, and this is considered by Murray to represent the thumbs, for according to his view the limb was composed of a pair of hands compounded by their radial sides. In the figure of the dorsal aspect which is given by Murray taken from a photograph, this protuberance cannot be clearly made out. The four radial fingers in size and shape appeared to be four fingers of a right hand. In the radial group of fingers, the " middle " and " ring " fingers (6 and 7) were webbed as far as the proximal joints, and the movements of the fingers of this group were somewhat stiff and imperfect. Between the two groups of fingers there was a wide space as between the thumb and index of a normal hand, and the two parts of the hand could be opposed to each other and folded upon each other. The power of independent action of the fingers was very limited. No single finger could be retained fully extended while the other seven fingers were flexed, but if both " index " fingers (4 and 5) were extended,

the other six fingers could be flexed, or the four fingers of either group together with the " index " of the other group may be ended, while the other three are flexed. The " index " fingers could not be flexed while the other fingers were extended, nor can the " little fingers " be extended while the others were flexed. Mi UKAY, J. JAKUINE, Med. Chir. Trans., 18G3, XLVI. p. 29, PI. n. 4! Mi. Female child, five weeks, having a hand of eight digits on the right side (Fig. C.i4). The digits were disposed in two groups of four in each. [No further

4.97 Female child having right hand almost exactly like MURRAY'S case, but without syndactylism. The two halves could be folded on each other. The four extra digits articulated with an imperfect metacarpal which was annexed to the normal metacarpal [of the index]. FUMAGALLI, C., Annul. Univers. di Mcd. Hilano, 1871, vn 1. ccxvi. ]t. 805, jig. Girl's right hand having eight fingers, represented in a wax model. LANGALLI, La scienza e lapmtica, Pavia, 1875 [Not seen : abstract from DWIGHT, I. c.].

498. DOUBLE-HAND III. Six digits in two groups of three and three. Man having abnormalities of left arm as follows (Fig. 95). The left hand was composed of six digits with three phalanges, which were disposed in two groups of three digits in each. The two middle digits were the longest (d3 and d*), and the length of the digits on either side of them diminished regularly. The appearance was us of a hand composed of the middle, ring and little fingers of a pair of hands united together. The two groups of fingers were to some extent opposed to each other and all the dibits could be flexed and extended. The digit d3 though single in its peripheral parts articulated with two metacarpals, its proximal phalanx having two heads. Upon the radial side of the

carpus of this hand there was a soft tumour about 2'5 cm. in height, resembling a cyst with a firm wall. FIG. 95. Dorsal and palmar aspects of the left hand of No. 498. The digits are numbered from the inside. The structure of the bones of the arm and fore-arm could not be made out with certainty in the living subject, but it appeared that the humerus was formed by two bones partially united together. As regards the skeleton of the fore-arm an ulna could be felt extending from the upper arm to the processus styloideus. The existence of a radius could not be made out with certainty, but a second bone could be felt which was in very close connexion [with the ulna]. JOLLY, Intermit Beitr. z. wiss. Med., 1891. 499. Male child, three years old, twin with a normal female child, having all extremities abnormal. Right hand. Six metacarpals arranged in two groups of three in each group. Each bore a three-phalanged digit, none resembling a thumb. The first and sixth were alike, resembling a minimus, while the two median fingers resembled middle fingers. On the radial side the three digits were completely united together. The next was free, and the two external to this were also united. Left hand. Like the right, but all the fingers united together in two groups of three in each group. Feet. Each foot had nine metatarsals and nine digits, the central being like a hallux and having two phalanges perhaps, but thicker than a hallux. The externals were like minimi. The four toes on each side of the " hallux " were united two and two. The tarsus was of about double size. The right leg was shorter than the left. GHERIXI, A., Gaz. med. ital.-lombard., 1874, No. 51, p. 401,,

*500. ^I;|" ('-vimim-d alive) having abnormalities in the digits of handami feet (Kiir. '.)(>). The ra^e is very briefly and inadequately described, Imt the c-Miirlit imi was a]i]>ai-i-iitly as follows. /,'/'//// I, n ml. IJcgiiining from the ulnar side, there were three i-inal dibits (i;, ."), 1). lit-yiiiid the third of these, which must be regarded as the medius, there were two complete digits (3, 2) each having three phalanges : and on the radial side of the innermost of these digits there was a stump-like rudiment (1), apparently representing another digit. [This case therefore differed from those of Win die and Rijkebiisch in the fact that both the digits internal to the media* (>/>) were disposed as though they belonged to a left hand, and KUHXT, in fact, states that each hand was, as it were, composed of parts of a pair of hands, thus agreeing with JOLLY'S case, No. 499.]

Left hand. In this hand there were only five digits, each of which had three phalanges. None of them was fully opposable, but that on the radial side (1) could to some extent be moved as a thumb. Of these five digits the middle one was the longest, and on each side of it there were two similar digits, those next to the middle finger being the longest and those remote from it being a good deal shorter and having the form of little fingers, which KUIINT considers them to have been. [This hand is perhaps in Condition II.]

Ri</ht foot. The hallux (2, 3) was of abnormal width and its bones were to some extent double, the ungual phalanx being completely so. [The nail however is drawn as a single structure and the double character of the toe was not apparent in its external appearance.] On the internal (tibial) side of the hallux there were two supernumerary toes (1, 1) having, so far as could be ascertained, a single metatarsus. The number of phalanges in these toes is not distinctly stated.

Left foot. The hallux (3, 4) was to some extent double, like that of the right foot. Internally to it were two supernumerary toes (1, 2) having apparently a common metatarsal. [Of these the most internal is represented as being very wide and resembling a hallux, but this feature is not mentioned in the description and the number of phalanges is not given]. [It is greatly to be regretted that no fuller account of this important case is accessible. According to KUHNT'S view each hand and each foot were structurally composed of parts of a complementary pair of hands and feet. As regards the hands the facts agree with this description and with what has been seen in other cases, but the condition of the feet is more doubtful, and without more knowledge of the details no opinion can be given. It should be remembered that the original description is very brief and Dr Kuhnt offers an apology for the imperfection of the figures.] KUHNT, Virch. Arch. f. path. Anat. u. Phys., LVI. 1872, p. 268, Taf. vi.

502. Man whose right arm beside the normal hand bore an extra thumb and finger. The two thumbs were united and had a common ruetacarpal joint. They were of equal size. They were flexed and extended together and had the power of spreading apart. The extra finger was beyond the extra thumb and was shaped like an index. Besides the radius and ulna of the normal arm there was an extra radius on the outer [? internal] side of the normal radius. Tin's bone had a joint of its own at its elbow. The wrist was broad, suggesting the presence of additional bones. Nothing is said of a metacarpal bone for the new index. CARRE, Seance pub I. de la soc. rot/, de Jfed., Chir. et Pharm. d>;

Tinleft labium niMJus was twice as large as the right, and the left !>•_' .mil thigh were much thinner than the corresponding parts on the right side [measurements given]. The extra parts were all on the plantw >ide of a toot which had toes of nearly normal shapes and sizes. This foot was Lent into a portion of extreme talipes equino-varus, and the great toe was bent so that it pointed inwards at right angles to the metatarsal. I'jMin tlir jilaiitar side of this foot there was a series of six wellformed, small toes, arranged in a series parallel to that of the 'normal' ti\e, and having their plantar surfaces in opposition to those of tinlatter. Of the series of six toes that facing the normal little toe exactly resembled it. The second was the longest of the six, but did not resemble a great toe. The third and fourth were equal in length, the lifth and sixtli being shorter, as are the external toes of a normal foot. None of the toes were webbed. BULL, G. J., Boston Med. and Sin-;/. Jour. iNT'i, xcni. p. 293, Jig. [This ligure copied by AIILFELD, Afissb. d. Men when, PI. XX. fig. 2.]