AN 1CHTHY0BDELLID PARASITIC ON SAND WHITING. 33 
and open on the second annulus of each segment. The 
diameter of the aperture of the nephridiopore is about 5 
In each segment the lateral canals receive three or four main 
branches, which are the outcome of the anastomotic canals. 
These latter are best developed around the ventral lacuna, but 
they also surround the dorsal lacuna. The arrangement and 
relative size of these canals is shown in PL 2, fig. 7. 
As is general in Hirudinea, the canals of this nephridial 
system are intracellular. The cells, which are burrowed 
through by these canals, have oval nuclei. 
The nephridiopores open directly on the body surface and 
not into pits, like those of Cystob ranch us. 
Neither in the living animal nor in serial sections have I 
been able to find internal openings, so that the ciliated 
funnels, possessed by Bran chel lion and Pontobdella, 
are here absent. In this respect then Austrobdella 
resembles Piscicola, Callobdella, Cystobranchus, 
Abranchus, and possibly Platybdella. 
This nephridial system is most like that described by 
Johansson for Callobdella. It differs in the much greater 
development of the branch going to the nephridiopore, and 
the greater degree of anastomosis of the smaller channels. 
In Austrobdella there exists on either side a fine canal, 
which may represent the dorso-lateral canal described for 
Callobdella. The lateral tubes are well developed in 
Austrobdella, being 40^ as compared with Abranchus 
and Callobdella 20 jjl, Piscicola 30 p , but again am 
smaller than Cystobranchus 50 /u (Johansson, 1896). 
Reproductive System. 
Thanks to the excellent work of Brumpt (1900), f Reproduc- 
tion des Hirudinees/ it is possible to compare the repro- 
ductive organs of Austrobdella with those of allied leeches. 
This species in its male organs resembles most Callobdella, 
(Trachelobdella) lophii as regards the structure of th& 
ejaculatory canal, but it lacks the muscular organ of Johansson 
VOL. 62, PART 1. — NEW SERIES. 3 
