118 
FKANK E. BEDDAKD. 
Acanthodril us there are large tubular glands opening close 
to, but quite independently of, the pores of the male reproduc- 
tive ducts. 
Of these glands there appear to be two different forms. In 
Perichseta, with the exception of P. Stuarti referred to 
above (p. 110, footnote), Perionyx, Megascolex, and in 
many of the Australian Lumbricids lately described by Mr. 
Fletcher ( 11 ), these glands, which have received from their 
position the name of “ prostate ” glands, are irregularly-shaped, 
lobate bodies ; they communicate with the exterior by means of 
a thick-walled, muscular duct, which receives at its upper ex- 
tremity the vasa deferentia. In Acanthodrilus, 1 Ponto- 
drilus, and in some other genera, the prostate glands are 
somewhat different in form ; they consist of a compact tubular 
gland, which is frequently coiled, but which, like the prostate 
gland of Perichseta, opens into a thick-walled muscular tube, 
which in its turn opens on to the exterior. With the upper ex- 
tremity of the latter, in Pontodrilus, is connected the vas 
deferens; in some other genera, on the contrary (Acantho- 
drilus) the gland preserves the same general appearance, and 
the same histological structure, but is unconnected with the 
vas deferens. 
In Eudrilus the apparent homologues of these glands are 
very different in their general appearance from those of any 
other Earthworm, so much so, in fact, that Perrier, their 
original describer, was inclined to doubt their homology with 
the prostate glands of other Earthworms. The glands in 
question are much larger than those of Acanthodrilus, and 
are straight instead of being coiled. Furthermore, they have 
a nacreous appearance, which is due to the presence of abun- 
1 Perrier’s figure of the prostate gland iu Acanthodrilus ungulatus 
(‘ Nouvelles Arch. d. Mus.,’ 1872, pi. ii, fig. 18, pr.) would seem to indicate 
that iu this species alone the prostates have the racemose characters of those 
of Perichseta. If, however, Horst (‘Notes from the Leyden Museum,’ 
vol. ix, p. 252) be right in assuming that my A. Layardi (‘ Proc. Zool. Soc.,’ 
1886) is really the same species, I can state most positively that they are like 
those of other Acanthodrilus. 
