136 
[No. 2, 
On the Osteology op Trllnops pebsicus, — by O. E. Dobson, B. A., 
M. B., Assistant Surgeon, H. M's British Forces. 
(With plate VI.) 
[Received and read 6th March, 1872.] 
The construction of the bony skeleton shows a closer relationship with 
Pliyllorhina than expected by me, when writing my description of the genus, 
founded on the typical species of which I had not then obtained a perfect 
skeleton. 
The genus is connected with Pliyllorhina, principally, in the relative 
number and length of the hones of the fingers, supporting the wing mem- 
brane ; in the relative number and length of the hones of the toes ; in the 
shape of the iliac bones ; and less markedly in the flattened form and verti- 
cal height of the nasal bones. In some other respects, especially in the form 
of the bones entering into the construction of the basis cranii, and in their 
foramina, its relations are more closely with Ithinolophus, while it differs 
from both genera, not less importantly, in some peculiarities of structure to 
be described hereafter. 
I shall, therefore, in describing the bones of the skeleton compare them 
generally with those of the species of Phyllorhina and Ithinolophus, and 
particularly with those of Ph. larvata, Horsf., portions of the skeleton of 
which are figured in the accompanying plate for the purpose of comparison. 
In its general outline the skull resembles that of Phyllorhina more 
closely than Ithinolophus, especially in the flattened form and less vertical 
height of the nasals, which are, however, relatively, much more developed 
laterally and vertically, than in the former genus. From both genera it 
differs remarkably in the form of the zygomata which are greatly com pressed , 
and expanded in a vertical direction. 
The superior margin of the zygoma rises vertically to a height of 015 
inch immediately in front of the posterior origin of the arch, maintaining 
this height for more than two-thirds its length, then suddenly narrowing to 
half near its connection with, the maxillary ; the inferior margin is straight, 
and the intervening bony structure very thin and diaphanous. The zygo- 
mata are not curved outwards, as in Phyllorhina and Ithinolophus, and then- 
flattened arches form straight lines with the sides of the maxilla-. 
The basis cranii is much narrower than in Phyllorhina ; the basi-occipi- 
tal is less than half the width of that of Ph. larvata, the total lengths of the 
skulls being, respectively, 085 and 095 inches. 
The following table of dimensions shows the principal measurements of 
the skulls in Tr. persicus and Ph. larvata : — 
