W. Nicoll 
291 
in the lungs and trachea but also in the mouth, gullet, and stomach. 
He remarked that it is most unusual to find the same species of fluke 
inhabiting both the respiratory and alimentary systems, an opinion 
which I can only endorse, except in the few cases in which the same 
parasite inhabits both the trachea and the oesophagus. The matter, 
however, is further complicated by Dr Sweet’s observation of the 
parasite in the intestine of the tiger snake, unless, as is not impossible, 
the stomach was regarded as part of the intestine. The most probable 
explanation of Dr Cleland’s finding the parasites in the peritoneum 
appears to be that the lungs were damaged on killing the snake or in 
dissecting it and that the parasites thereby made their escape into the 
peritoneal cavity. 
In my original description of Dolichopera parvula, from the carpet 
snake, the habitat was recorded as the intestine, but this should in 
reality have been the oesophagus. It is possible that a similar lapsus 
may account for Dr Sweet’s observation in the case of the tiger snake. 
Taking everything into consideration therefore it seems most probable 
that the normal habitat of these two species is the lungs, trachea and 
oesophagus. As already noted a similar habitat is met with in the case 
of certain other Trematode parasites of reptiles. 
McAlpine describes the colour of the parasites as “quite black." 
This, however, only applies to the older specimens in which the dense 
mass of the uterus fills almost the entire body, leaving only a narrow 
clear rim round the margins. In less mature specimens, and particularly 
in those from the tiger snake, the general colour is dark brown. 
The parasite is moderately flat, elongated oval in outline, with 
rounded ends. The posterior end is frequently drawn out into a short 
tip-like projection. In addition there is not uncommonly a slight 
constriction just behind the ventral sucker. The surface of the body 
is covered with fine spines which extend to within a short distance of 
the tip of the tail. 
The length varies from 2-6 mm. to 3-5 mm. (average 3-1 mm.). 
The maximum breadth, which occurs at the level of the ventral sucker, 
is 1-0-1-6 mm. (average 1-25 mm.). The length is therefore about 21 
times the breadth. 
The subterminal oral sucker is fairly conspicuous and measures 
0-315-0-465 mm. in diameter. The ventral sucker lies almost exactly 
in the centre of the body, or a very short distance behind it. Its outline 
is generally somewhat obscured by the uterus. It is smaller than the 
oral sucker, measuring only 0-25-0-45 mm. in diameter. 
