1894.] 



MAMMALIAN HAKD AiSTD FOOT. 



375 



Hand. 



Scaphoid. Eadiale. 



Pros. row. 



Centrale. 



Lunatum. 

 Triquetrura 

 (pyramid.). 

 (Pisiform.) 



Centrale. 



Intermedium. 



Ulnare. 



Foot. 

 f Naviculare tib. "I 



/KarSfkrefib. f Na ™ ulare - 

 I Oat). J 



Talus s. 8. 



m • _ [ Astragalus, 



lngonum. [ ° 



(Calcaneum.) 



As regards the distal row there cannot be any doubt that the 

 trapezoid and uncinatuni are homologous with the middle cunei- 

 form and the cuboid. 



As the internal cuneiform (Erethizon, Man sometimes) and the 

 external (Cn/ptoprocta) can be divided into two bones, we must look 

 for the homologous bones in the hand ; and I think that the radial 

 part of the trapezium (sometimes a free ossicle in Man) corresponds 

 to the tibial or the plantar internal cuneiform, and that the head 

 or proximal part of the magnum (Man), or the lateral part of the 

 centrale (e. g. Centetes), corresponds to that bone which is situated 

 proxiinally to the external cuneiform in Cryptqproeta. I cannot 

 prove beyond all doubt that this is the second centrale, but there 

 seems to be no other explanation. Consequently the distal row 

 would be as follows : — 



Hand. 

 Trapezium. 

 Trapezoid. 

 Magnum. 



Unciform, 

 (separated : 

 Ziphius). 



Carp. tars. dist. 1. 



Carp. tars. dist. 2. 

 f Carp. tars. dist. 3. 

 \ Centrale 2. 

 I Carp. tars. dist. 4. 



Carp. tars. dist. 5. 



Foot. 



T , -i ./. f Plan tare. 



Internal cuneiform. \ ^ , 

 [ Dorsale. 



Middle cuneiform. 



f External cuneiform s. s. 



\ Triangulare, B. 



Cuboid. 



P.S. {April 23, 1894). — Since I read this paper I have found a 

 specimen of Euphractus minutus in the Nat. Hist. Museum in 

 which there is a very well-developed prsehallux, like a metatarsal 

 bone (see Plate XXI. fig. 7). There is also a muscle between the 

 Ph. and the first metatarsal bone. 



EXPLANATION OF THE PLATES. 



Plate XX. 



Skeleton of Mammalian Hands and Feet. 



Fig. 1. Eight foot of Dasj/pus, 3/2 enlarged (p. 356). 



2. Eight hand of Centetes ecaudatus, 3/2 enlarged (p. 356). 



3. Eight foot of Centetes ecaudatus, 3/2 enlarged. 



4. Eight foot of Bathycrgus maritimus, 5/3 enlarged (p. 356). 



5. Eight foot of Erethizon dorsatus seen from above, nat. size (p. 357). 



6. Praehallux of Erethizon, seen from behind, 3/1 enlarged. 



7. Eight hand of JElurusjulgens, 5/4 enlarged (p. 358). 



8. Eight foot of Mlurus fulgens, nat. size. 



9. Astragalus of Mbirut seen from behind, showing the division into 



" talus " s. s. and " trigonum." 



25* 



