B. G. Wilder on a foetal Manatee and Cetacean. 112 
tween the Cetacea a the other Mammals, upon which Murray 
has so strongly insisted. 3, 55, 196 and 203.* 
As to the zodlogical status of the Sirenia, if the views above 
advanced are correct. there would seem to be no more ground 
for their removal from the Ungulata than for the separation_of 
the Pinnipedia as an order apart from the Carnivora. Nor 
would the comparison be invalidated by the view that the seals 
may be upon the upward rather than the downward path. 
he limits of this preliminary paper will not allow the dis- 
cussion of the relations of the Sirenia with special ungulate 
families and genera, or of the relative position of the sirenian 
genera.t 
But there is one point of resemblance between the Sirenia and 
the Proboscidia upon which, it seems to me, undue stress is lia- 
ble to be placed, namely: that in both groups the mammary 
glands are pectoral or axillary, while in the hippopotamus they 
are inguinal. 
The consideration of the variations as to number and 
position of these organs in other groups shows, however, that 
in recent times they have never been regarded as of sufficient 
taxonomic value for the determination of ordinal or even 
family affinities. (For instances, see Owen, 12, iii, 775-730.) 
_ it may at first seem strange that there are no traces of hinder 
limbs in this foetus, and that the front limbs are not more like 
the legs of its supposed quadrupedal ancestors. ; 
It is by no means impossible that an embryo just forming 
would present rudimentary hinder limbs in accordance with the 
usual vertebrate type. 
s to the manus, it is to be borne in mind that the vast ma- 
jority of existing vertebrates + have anterior limbs which vary 
but slightly from the pad-like form which they present in the 
* With the Cetacea it is said that “ the apex of indented,” 
(Owen, 12, iii, 521). But we need further information upon this point and also 
specting the statement of Gratiolet,(16,) that a like condition prevails in the 
ene: : will be me 
am inclined to think that a careful study of embryos and brains will be more 
satisfactory than even such exhaustive osteological comparisons as those of 
PE Fgh 4 fishes, many batrachians, some reptiles, all birds, and a very 
