Haswett—A Monograph of the Temnocephalee. 129 
The vagina in Zemnocephala is simply the passage leading from the ootype to the 
genital cloaca, by which the egg passes to the exterior, and into which, probably, the 
cirrus is received in copulation. In general its walls, though less muscular, resemble 
those of the uterus ; but in the New Zealand species (PI. x1v. fig. 3) the structure is 
very remarkably modified. Here the vagina is a rounded muscular organ of 
relatively large size, forming, next to the cirrus, the most conspicuous part of the 
reproductive apparatus. Its walls consist of two great masses of muscular fibres, and 
on its inner surface are a great number of larger and smaller pointed chitinous teeth. 
Unless 7. Semferi is very unlike the Australian forms, Max Weber has fallen 
into an error in confounding together the ootype and the genital cloaca, and 
describing and figuring them as one cavity.* He has therefore interpreted wrongly 
the position of the shell-glands and their ducts. He says (p. 16)—‘ Schliesslich 
geht der Oviduct in den Uterus iiber, nachdem er sich vorher mit dem Cirrusbeutel 
vereinigt hat, der schriig in ihn ausmiindet. Obwohl wir es mithin von jetzt ab mit 
einer Geschlechtskloake zu thun haben, durch die der Cirrus sowohl nach aussen 
gebracht als auch die Kier abgefiihrt werden miissen, méchte ich dennoch einen in die 
Quere erweiterten Raum, der kurz vor dem Genitalporus—der Ausmiindung der 
Geschlechtskloake—liegt, Uterus nennen.” 
A number of the unicellular glands open on the surface immediately around the 
5 
genital opening as already described. The ducts of these glands are not always 
distinguishable, as they are not readily to be seen unless the secretion is passing 
through them ; when this is the case they become extremely conspicuous in sections 
5 ? 
being very numerous, situated close together, and presenting here and there little 
5 ? co) 
dilatations. It is probable that these glands have the function of secreting the 
viscid material by means of which the eggs after they are discharged are affixed 
together and to the surface of the Crustacean. Weber ascribes this function to a 
group of strings of cells opening immediately round the genital opening. There are 
no such structures in the Australian species. 
The vitelline glands (PI. xv. fig. 2, v.) attain a high grade of development in 
the Zemnocephalee. They are closely adherent to the intestine, and cover nearly the 
whole of its dorsal surface, extending round the margins to encroach more or less on 
the ventral surface also. They consist of a series of narrow lobes, which anastomose 
occasionally so as to form an irregular network. In certain of the Australian species 
the lobes are arranged in irregular transverse lines following the divisions of the 
intestine, and thus presenting a rudimentary metameric arrangement. In longitu- 
dinal sections it is found that the muscular septa of the intestine pass outwards 
* Loc. cit. p. 16: Tab. 1. fig. 1, and m1. fig. 11. The same error, if it be an error and not a specific difference, is 
committed by Semper. 
8 
