1909. ] ANATOMY OF CERTAIN UNGULATA. 189 
the cecum. The colon as it leaves the cecum shows hardly any 
trace of the paracecal flexure so common in these animals. 
There is practically no twisted section of colon at this point. 
Furthermore, the colic spiral is very much reduced, a fact which 
one naturally associates with the small size of theanimal. It isin 
fact, as the accompanying text-figure shows (text-fig. 13, p. 183), 
no more complicated than in the Lorisine Lemurs*, which show 
the simplest colic spiral known to me. A transverse section 
across this spiral would in fact only divide the colon five times. 
This of course recalls the diminutive spiral of the Chevrotains 
described by Milne-Edwardst and more recently by Mitchell $. 
It is to be noted, however, that the spiral in Zragulus (see text- 
fig. 14, p. 184) is rather different from that of Jadogua. For in 
the latter the spiral is flat, and is separated from the cecum by 
the ileum to which it is attached by mesentery, just as the ileum 
in its turn is attached to the cecum by a band of mesentery. In 
Tragulus the small spiral is fixed on to the cecum near to its 
colic end. It appears to me possible that this spiral in 7ragulus 
is not the precise equivalent of that of other Artiodactyles, but is 
the ansa paracecalis which tends to show a spiral form in many. 
For example, in the small Antelope Cephalophus abyssinicus, of 
which I have lately dissected an example, the ansa paraceecalis was 
much more conspicuous and complicated than that of Madoqua 
and tended towards a spiral arrangement; so too with Moschus 
described and figured above. It may also be that the distinctly 
spiral commencement of the ansa paracecalis in Hyrax§ is 
referable to the same category, as is also that of many Rodents. 
There is, however, some variation in the colic spiral of 
Ruminants which may be a question of age or of actual variation. 
I have pointed out that in the Rodent Hydrochawrus|| the younger 
individuals have a rudimentary spiral which later becomes large. 
I have examined this spiral in two examples of the Antelope 
Tragelaphus scriptus, both females. In one specimen the coils 
were hardly more complex than in Madoqua. The colon consisted 
in this region of four loops each consisting of two limbs, so that a 
transverse section across this region of the gut would divide the 
colon eight times. On the other hand, the second specimen had 
a more complex colic spiral. 
I may observe that the close connection of the small intestine 
with the colon—for the former gut is attached by mesentery to 
the colon for some distance after the colon has emerged from the 
colic spiral—is a feature often (? always) found among Artio- 
dactyles; it is paralleled in a remarkable way in the Beaver, 
another fact illustrative of the numerous structural resemblances 
between the Rodents and Ungulates. 
* Beddard, P. Z.S. 1908, p. 578, and literature therein cited. 
+ Ann. Sci. Nat. 1864. 
t Trans. Zool. Soc. vol. xvii. p. 472, fig. 19. 
§ P.Z.S. 1908, p. 532. 
|| P.Z.S. 1908, p. 537. 
