1894.] MAMMALIAN HAND AND FOOT. 355 



A.— ON THE SKELETON. 



As the pisiform and the calcaneum are present in all mammals, 

 and as it is of no importance whether these bones are large or small, 

 and whether they are directly connected with the ulna or the fibula, 

 or not, I will not give here details on this point. Nobody will 

 doubt that these bones are constant and that the large pisiform of 

 lower mammals is homologous to the smaller one of the highest, 

 e. g. Man — nor that the calcaneum of Monotremata, though it is 

 directed forwards or outwards, is homologous to the calcaneum of 

 higher mammals, where it is always directed backwards. Further, 

 1 must recall what I published in these Proceedings in 1889, 

 that the pisiform is divided into two pieces in Bathyergus, being 

 the only animal in which I met with this separation. 



As I cannot tell here the names of all mammals in which I 

 have found the Pp. and Ph., I will only mention those in which 

 I made a sketch or measured these structures. 



I am sorry I did not pay attention to the carpus and Pp. in my 

 first investigations made in 1885 in Berlin, when I examined the 

 mammalian foot for the " intermedium tarsi " or " os trigonum." 



To the names of the animals which I examined in London, 

 Berlin, Leyden, and other places I put the letters Lo., Be., Le., 

 Pa. (Paris), Je. (Jena), A. (Amsterdam), Br. (Brussels) ; otherwise 

 London, especially the Nat. Hist. Museum, is intended. I use the 

 following abbreviations : — long or length 1., breadth br., thickness 

 th. ; do.-vo. (dorso-volar), do. -pi. (dorso-plantar), sag. (sagittal), 

 tr. (transverse), r. (right), 1. (left) ; = no, or not present. The 

 numbers mean millimetres. 



N.B. — As the Pp. and Ph. are often lost in preparing and cleaning 

 the skeletons, I am often doubtful whether a Pp. or a Ph. had 

 been present (and lost) or not. In such cases I put a " ? ". 



Maesupials. — The Pp. is situated on the trapezium (carp. dist. 1), 



the Ph. on the internal cuneiform. 

 Macropus (Halmaturus) bennetti : Pp. 

 Trichosurus vulpecula : Pp. 



Phascolomys ivombat : Pp. 7 1. ; 4 br. ; 3 do. -vol. 

 (Be., Lo.) Didelphys marsupialis [cancrivora, Be., Je. ; aurita, 



Be.] : Pp. Ph., 4-5 1. ; about 3-0 br. ; 2 do.-pl. " D. aurita " : 



5 1.; 3br. ; 2 th. 

 Didelphys elegans : Pp. Ph. consists of two bones ! 

 (Be.) Didelphys azarce : Pp. Ph. 

 Didelphys philander : Pp. Ph. 

 Didelphys crassicaudatus : Pp. Ph. 

 (Le., Be.) Ohironectes minimus (yariegatus) : Pp. Ph. 2*5 1. ; 



1-8 do.-pl. ; 1-2 br. 



Edentata. — The Pp. is attached on the scaphoid and trapezium ; 

 the Ph. on the naviculare and first cuneiform. 

 (Be., Lo.) Tamandaa (Myrmecophaga) tetradactyla : Pp. Ph. 

 (Be.), 10 1. ; 5-6-5 do.-pl. ; 2-5 sag. 



