110 
Queensland Trematodes 
Family Eehinostomidae. 
Sub-Family Echinostominae. 
Echinostomum acutieauda n. sp. 
(Plate VI, fig. 4.) 
A considerable number of specimens of this parasite were found in 
the cloaca, rectum and lower intestine of the straw-necked ibis ( Car - 
phibis spinicollis). It is a long, narrow, flat and delicate species, from 
9 mm. to 12 mm. in length. The breadth is fairly uniform, 0'9 to 
TO mm., i.e. about one-eleventh of the length. The tail terminates in 
a very sharply pointed tip. The width of the head is 0‘6 mm. and there 
are 37 cephalic spines measuring 0T to 0T12 x 003 to 0035 mm. 
The neck is closely set with cuticular spines." Behind the ventral sucker 
to the level of the testes there are a number of small scattered spines. 
These disappear from the margins of the body not far behind the sucker 
and are also absent on the dorsum. 
The oral sucker measures 0 - 2 to 0’21 mm. in diameter. The ventral 
sucker is deep and measures 0’7 to 0‘77 x 0'56 to 0 - 63 mm., the average 
being 0’73 x 0'59 mm. It is situated at a distance of T2 to 1'5 mm. 
from the anterior end, i.e. a little more than one-eighth of the body 
length. The oval pharynx measures 0T8 x 0T4 mm. and the oeso¬ 
phagus 0'43 mm. The diverticula are continued to near the posterior 
end. 
The genital aperture is situated over the intestinal bifurcation. 
The cirrus-pouch is stout and nearly reaches the centre of the ventral 
sucker, on the dorsal surface of which it lies. Its dimensions are 
0'4 x 03 'mm. It contains a large convoluted vesicula seminalis, a 
small pars prostatica and a short ductus. 
The small round ovary is situated at a distance varying from 0 - 9 mm. 
to 2 - 45 mm. behind the ventral sucker. On an average the distance 
is 1’5 mm. It measures 0’23 x 0'27 mm. The anterior testis is about 
0'25 mm. behind the ovary and it is separated from the posterior testis 
by a space of about OT mm. The testes are long, narrow and somewhat 
sinuous. Their edges are much indented. The posterior testis is 
invariably the larger. On an average they measure 083 x 0'37 mm. 
and 096 x 033 mm. respectively. The distance from the posterior 
testis to the tip of the tail is 4'05 to 4'75 mm. (average 4 - 33 mm., or 
exactly three-sevenths of the body length). 
