1889. | ANATOMY OF RHINOCEROS SUMATRENSIS. 9 
Rhinoceros were kept for some weeks while the muscles were in 
course of dissection. 
In performing this task we were greatly assisted by Mr. Tonks, 
now Physician at the Free Hospital, Grays Inn Road; for most of 
the drawings which illustrate this paper (woodcuts, figs. 3-10) we are 
also indebted to that gentleman. 
Both the individuals were referred on their arrival at the Gardens 
to Rhinoceros sumatrensis; subsequently Mr. Sclater considered 
that they were probably examples of his species Rhinoceros lasi- 
otis, of which the type is still living in the Gardens. Without 
going fully into the question of the distinctness of Rh. lasiotis from 
Rh. sumatrensis, which cannot be done properly until the death of 
the type specimen, it may be remarked that there are uo characters 
in the skull which would seem to justify such a distinction. In 
making a comparison of the skull of these specimens with RA. 
sumatrensis, particular attention was paid tu a paper by Prof. Flower 
in the ‘ Proceedings’* of this Society, in which a skull possibly 
identical with Mr. Sclater’s 2th. dasiotis was compared with Rh. 
sumatrensis. Assuming that problematical skull to represent RA. 
lasiotis, it is clear that neither of the individuals discussed in the 
present paper belong to that species, for in all the points raised by 
Prof. Flower these individuals are typical Ih. sumatrensis. 
With regard to the visceral anatomy of this species we have not 
much to add to the description by Garrod ; and the species does not 
differ materially from Rh. sondaicus, which we have described some- 
what fully in the ‘ Transactions’ (vol. xii.) of this Society. 
Garrod describes the ridges upon the hard palate of RA. sumatrensis 
but gives no figure of it. The accompanying drawing (fig. 1, p. 8) 
has been made for the purpose of a comparison with the hard palate 
of Zh. sondaicus, which has been figured by us in our memoir upon 
that Rhinoceros. 
The cecum and the neighbouring parts of the intestines have been 
figured by Garrod ; and as his figure illustrates the principal points 
in the anatomy of this region of the gut, we have thought it hardly 
worth while to give a further illustration. 
In the loop which is formed by the commencement of the colon, 
the distal portion is of a narrower calibre, as shown in Garrod’s 
figure. 
The mesentery which unites the opposite sides of the loop has a 
peculiar fold upon it which is illustrated in our figure of Rh. 
sondaicus. Inthat Rhinoceros the fold in question (/oc. ett. pl. xxiv. 
figs. 1-3) arises near to the ceecum and receives a branch from one 
of the divisions of the colic artery ; at the opposite extremity of the 
colic loop the band divided into two, which were attached to the 
surface of the mesentery uniting the parietal sections of the colon ; 
at this point the artery borne by the fold also divides and becomes 
continuous at two points with the colic artery. It appeared to us 
at the time we were investigating the anatomy of Rh. sondaicus 
that the azygos artery borne by this fold might serve to supply this 
; 1 P, Z. 8. 1878, p. 634. 
