432 MONOGRAPH OF THE TEMNOCEPHALE.K : SUPPLEMENT, 



Temnocephala CiECA, n.sp. 

 (Plate xxii., fig. 4.) 



This species resembles the great majority of the members of 

 the genus in the possession of five tentacles of equal, or nearly 

 equal, length. It is quite white, and has no trace of eyes. The 

 intestine is devoid of constrictions or septa. The posterior testes 

 are situated altogether behind the intestine : they are of irregular 

 rounded shape with a short inwardly projecting process from 

 which the vas deferens is given off. The anterior testes, which 

 lie at the sides of the intestine, are smaller than the posterior and 

 are somewhat compressed laterally. 



The penis is remarkable for the strong backward curvature of 

 its tubular portion, a feature in which it differs from that of all 

 the other known species. The introvert is not very distinctly 

 separated off : it is beset with a number of very tine spines. 



I am indebted to Prof. W. Baldwin Spencer for sending me 

 living specimens of this species, which he had noticed on the 

 surface of the remarkable burrowing Isopod described by him 

 and Mr. T. S. Hall under the name of Phreatoicopsis* They 

 were found about twenty miles south of Colac in Victoria. 



The Temnocephaleae in general. 



In an important paper f recently published by Monticelli 

 entitled " Sulla Temnocephala brevicornis, Mont. (1889) e sulle 

 Temnocefale in generale," there are one or two misconceptions of 

 importance which I take this opportunity of correcting. One of 

 these relates to the position of the penis. Monticelli has fallen 

 into a curious error with regard to this point. He seems, on the 

 strength of his interpretation; of two figures in my first paper 



* Proc. Eoy. Soc. Vict. 1896, p. 12. 



f "Bolletino della Societa di Naturalisti in Napoli." Annoxii. Vol. xii. 

 (1898). For a separate copy of the paper I am indebted to the author. 



X The interpretation was incorrect. One of the x -Jfigures in question is a 

 diagram of the general organisation of Temnocephala, the animal being 

 looked at from the ventral side. The other is a transverse section with its 

 posterior surface upwards, it being one of a series cut from behind forwards. 



