1885.] Zoblogy. 195 
ON THE CENTRALE CARPI OF THE MAmMALS.—Professor H. 
Leboucq, in his “ Recherches sur la morphologie du carpe chez les 
mammifères,” Arch. de Biol. Tom. v, 1884, pp. 35—102, pl. 111—-vI, 
as made extended communications on this subject. I will add 
some observations, which will complete Leboucq’s results. In 
this present communication I will speak of the centrale only, 
and will defer other points discussed by Leboucq to a future ex- 
tended paper on the morphogeny of the carpus and tarsus of the 
vertebrates. I have found, like Leboucq and others, a distinct 
central bone in man, dog and cat. I regret not having been able 
to examine embryos of bats and marsupials. I can distinguish a 
centrale in two other specimens of Carnivores, in an embryo of 
Lutra of 50" and in an embryo of Mustela vulgaris of 
about 25™™ In Lutra the central bone was quite free and very 
fully developed, the radiale and intermedium were coalesced. In 
medium, at that part contiguous to the radiale. In Lutra the 
radiale and intermedium were entirely coalesced, in Mustela I 
found traces of a former separation. 
~ In an embryo of Erinaceus europeus of 65™™ I found no 
sign of a free centrale and no indication of a confluence of the 
bone with the radiale. The first tarsal row consisted of two 
pieces of cartilage, a radiale and intermedium, and an ulnare. In 
an adult Erizaceus collaris I observed the same condition as in the 
embryo. As in the different families of Insectivores, even in the 
adult state, a free centrale may be found or not, I do not hesitate 
to believe, that in all Insectivores in which a centrale has not yet 
n seen, such a bone will be discovered in embryos at some 
early stage of their development, 
In regard to the Marsupials I have had ‘no opportunity to ex- 
amine the embryo." In the manus of the following adult Mar- 
supials I can distinguish an os centrale coalesced with the radiale, 
as Leboucq has stated, viz: Didelphys azare, Perameles lagotis 
and Dasypus maculatus. Further I can state the same for Orni- 
thorhynchus and Myrmecophaga tetradactyla. 
A centrale carpi is therefore now shown to occur in all orders 
of mammals except the Ungulata and the Cetacea. 
Hyrax capensis possesses, as is well known, a free central bone. 
Professor Cope places the Hyracoidea together with the Con- 
dylarthra inthe order Taxeopoda, and considers these the oldest 
ungulates. If there is a free centrale in one of the oldest ungu- 
lates, Hyrax capensis, such a bone should exist in the allied forms 
of this and in the descendants of the Taxeopoda, and I have no hesi- 
l Since writing the above, I have distinguished in an embryo of Didelphys, 
nks fessor H. Osborn 
9.5mm long, a partially free central bone. My thanks are due Pro 
for the opportunity of making the examination, 
