116 Mr. F. E. Beddard on the 
have a large terminal sac; but this lies along the transverse 
axes of the body in close contact with the septa and 1s 
furnished with a cecum which lies on the distal side of the 
external pore. 
Perrier has indeed remarked that the posterior nephridia of 
Anteus gigas are Jess in calibre than the anterior and are 
attached by a membrane not represented in the anterior series ; 
but he says nothing of the cecum (supposing it to exist in 
that species). 
It is frequently the case in this family of earthworms 
(Geoscolecidee) that the anterior nephridia differ in structure 
from the posterior. In Rhinodrilus Gulielni* precisely the 
same differences exist as in the present species. 
The present species of Anteus, like the other species of the 
genus and like so many other earthworms, has several 
specially thickened septa lying in the anterior region of the 
body. In Anteus heterostichon there are four of these imme- 
diately following the gizzard and separating segments vi./vii., 
Vil./Viil., vill./1x., 1x./x.3; behind these is another, thinner, 
septum which largely covers the septum in front, just as these 
cover each other successively in the way that Perrier has 
described. 
Species of Anteus. 
Is the above species really distinct from Anteus gigas 
described by Perrier, and more recently by Horst? I am 
convinced that it ¢s distinct, and, moreover, I believe that 
Horst’s species is not the same as either Perrier’s or the one 
that I have just described. 
The points of difference between Anteus heterostichon and 
Anteus gigas are of course to be found mainly in the diver- 
gence of the sete posteriorly and in the commencement of the 
posterior set of nephridia in the thirteenth instead of the 
twentieth segment in the latter species. There can be no 
confusion as to these points, as Perrier’s description is perfectly 
clear. With regard to the sete he says (p. 52), “ Les soies 
sont disposées, comme chez le Lombric ordinaire, en quatre 
rangées de paires, deux rangées sont franchement ventrales, 
deux latérales. Ces rangées sont constamment paralléles 
dune extrémité & lautre du corps, et les soies de chaque 
paire sont toujours trés-rapprochées l’une de l’autre.” 
Dr. Horst considers that the species which he investigated 
is Anteus gigas. But in that form, as in Anteus heterostichon 
* Beddard, loc. cit., woodcuts figs. 5 and 6, 
