264 WILLIAM BLAXLAND BENHAM. 
In Anteus, Titanus, Rhinodrilus, no spermathece are 
known, nor are they certainly known in Moniligaster, but 
the genital system is so complicated and peculiar in this form 
that it demands further study. 
In Acanthodrilus, Pontodrilus, Digaster, Pleuro- 
cheta, there are two pairs of spermathece in somites vir and 
Ix, Opening anteriorly; in the last form are they bilobed, 
each having a smaller sac-like protrusion from its side as in 
Pericheta. In Perionyx, the spermathece are two pairs 
of simple sacs, in somites vit and vii1, open to the exterior close 
to the middie line. 
In Urocheta the spermathece are also simple pyriform 
sacs, six in number, lying in somites vi1I, 1x, x, and opening 
in a line with the third setz. 
In Plutellus the spermathecal pores are in a line with the 
third sete ; the spermathece are in somites V, VI, VII, VII, and 
Ix, open anteriorly, and each consists of a sac and a coiled 
accessory portion. 
It is in the genus Perichexta that these organs become most 
complicated. In P. elongata there is only a single pair, opening 
between somites 1v and v; each consists of asimple sac. In 
P. affinis, P. cingulata, and P. posthuma, each sperma- 
theca has a small secondary globular sac at its side, and there 
are four pairs placed in somites vi to 1x. In P. quadragen- 
aria and in Horst’s species from Java, there is a narrow coiled 
tube opening into the neck of the spermathecal sac; in the 
former there is only one pair of spermathece, and they are 
placed in somite vil. 
In P. Houlleti the spermatheca consists of three parts, a 
large sac, a coiled tube, and a smaller sac. 
In all these cases these parts have a common external pore, 
but in P. robusta there are these three parts, of which the 
small sac-like portion opens separately by means of a pore, just 
behind the true spermathecal opening. Again in P. asper- 
gillum the spermatheca has numerous very small sacs around 
it, each having a separate pore to the exterior. 
It seems to me that the numerous species of Pericheta may 
