BY WILLIAM A. HASWELL. 433 



on Temnocephala (Q.J. Micro. Sci. (2) Vol. 28) to have come to 

 the rather odd conclusion that I had mistaken right for left 

 throughout, and that when I stated that the penis of the Austra- 

 lian species is in all cases on the left, I meant on my left and on 

 the right of the animal ! Accordingly in the synoptical table of 

 the species which he gives at the end of his paper he divides the 

 species of Temnocephala into two groups — the group of American 

 species with the penis on the left, and that of "Oceanic" species 

 with the penis on the right. 



In his account of the male reproductive apparatus in T. brevi- 

 cornis, Monticelli (I.e. p. 81) states that on each side there are 

 two ducts, one from the anterior testis and one from the posterior, 

 and that these unite to form a main duct, right or left as the 

 case may be — the arrangement being similar to what I have 

 described as existing in Actinodactylella. He conjectures that 

 this may be universal in Temnocephala. But, as stated and 

 clearly figured by Weber in the case of T. Semperi, and by me in 

 the case of the Australian and New Zealand species, the usual 

 condition is quite different from this. In all these species the 

 anterior testis is joined directly to the posterior by a short duct, 

 and a single vas deferens is present on each side, coming off from 

 the posterior testis, but really acting as the efferent duct of both. 

 This is rendered clear enough by figures already published, but 

 the portion of a horizontal section of T. fasciata represented 

 in fig. 5 will still further illustrate the arrangement. The same 

 holds good of T. minor, T. Dendyi, T. comes, T. quadricornis, T. 

 Novce-Zelandice, T. aurantiaca, T. Tasmanica, T. cceca and Cras- 

 pedella Speuceri. 



It would thus appear as if we must admit the existence of an 

 important difference in structure between T. brevicornis and the 

 Australasian species. But I think that Monticelli's statement 

 and figure may be interpreted in another way. I think that 

 what he looks upon as the duct of the anterior testis may be in 

 reality the strand of ducts of the granule glands, which he says 

 he was unable to find. The glands in question are mainly situated 

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