28 
Trematodes of North Queensland 
This species bears a certain resemblance to Distomum levenseni 
described by Linton (1907) from Bermuda fishes {Epinephelus maculosus 
and E. striatus). From Linton’s descriptions and figures (Figs. 80 and 
81), however, it is almost certain that under the name D. levenseni he 
has included two entirely distinct species differing markedly from each 
other in the extent of the yolk glands and in the size of the ova. In 
the one the yolk glands extend more than half the length of the body 
and the eggs measure 0-065 x 0-04 mm. In the other the yolk glands 
are confined to a small area at the level of the ovary and the eggs 
measure only 0-046 x 0-023 mm. 
In regard to the relation between these American species and 
Aephnidiogenes barbarus it is evident that all three display a close 
resemblance in body form and in the size and position of the suckers. 
The alimentary system is also very similar, the diverticula in all three 
displaying the tendency to avoid the margin of the body and keep closer 
to the mid line. On the other hand in the American species the genital 
glands are situated much nearer the posterior end and the testes are 
distinctly tandem. The position of the uterus, again, is not quite 
identical. 
By the kindness of Professor Linton several specimens of Distoni^im 
levenseni were forwarded to me for examination. They all belong to 
the type with extensive yolk glands and large eggs. From this material 
I was able to confirm the details of Linton’s description and also to 
determine that the structure of the terminal male genitalia agreed in 
all essentials with that in Aephnidiogenes barbarus. There can, there¬ 
fore, be little hesitation in including Distomum levenseni in the genus 
Aephnidiogenes. 
The difficulty still remains of determining which of the American 
forms is to be regarded as Distomum levenseni. In his general description 
Linton specifically mentions that the yolk glands extend throughout 
the greater part of the body behind the ventral sucker, but no mention 
is made of the size of the ova. This appears to be sufficient ground for 
regarding the form with extensive yolk glands as the true D. levenseni, 
especially as this was the form submitted to me as such. The fact that 
the form with abbreviated yolk glands appears first in the list of illustra¬ 
tions does not seem of much weight. I regard this form as a distinct 
species and for it I propose the name Aephnidiogenes ptochus n. sp. 
The diagnosis of the two forms may be summed up as follows: 
Aephnidiogenes levenseni (Linton). 
Length 0-95-3-45 mm.; breadth 0-4-0-6 mm., cuticle covered with 
