to) CALIFORNIA ACADEMY OF SCIENCES. 
genus, and average about twice or three times as close as in Deltania Troyert. 
This is a prominent and constant characteristic. The characteristic feature of the 
genus, which consists in the narrowing together of the ventral setze on both sides 
and towards the male pore in xvii, is readily seen in this species. On account of 
the already very close approach of the ventral setee of each couple, this narrowing 
together is, however, less perceptible in our present species, but it is still consider- 
able and readily seen. The figure (fig. 40) will illustrate this better than any 
lengthy description. Not only does this approach of the sete exist on both sides of 
the male pore, but it is also seen towards the spermathecal pore, though here in a 
smaller degree. In Deltania Troyeri, there is not a trace of such an increased ap- 
proach of the ventral setee towards the spermatheeal pore. Another characteristic as 
regards the setae is that the ventral or inner couples are much closer together than 
in the other two species described here, so close that the main bodies of the sperma- 
thee almost touch. 
The spermathecal pore is situated in the intersegmental grooye between vili 
and ix, in front of seta 1. In Deltania Troyeri, the spermatheeal pore is in front of 
the corresponding seta 1, but considerably more lateral, and on account of the 
greater distance of the ventral couples of setae, the spermathece in that species are 
much further apart, and do not crowd the ventral ganglion. Ovidueal pore as usual 
in xiy. Penial setze on papille in xvii, opening in the male pore. The clitellum 
comprises three full and wide somites, xiv, xv, xvi, and two smaller ones, xii and 
XVli, as in other species. 
The genital region (fig. 48) around the male papillee is much simpler than in 
Deltania Troyeri. The two papille are situated much closer together, and there are 
no suctorial depressions with their fan-shaped arrangement of muscles. The penial 
setee are very slender, sickle-like, bent at the free apex, with a narrowed and sharp 
point. There are a dozen or more external fibres of exceeding thinness stretching 
from the anterior part of somite xvii to the posterior part of xvii. These 
threads, however, exist only in the longitudinal groove between the papillee, all run 
parallel with each other and with the long axis of the body (fig. 48). As to their 
nature Tam not at all certain. They are apparently too thin to be muscles. The 
clitellum proper in this as in the preceding species ends at the papillee or male pore. 
Anterior to it the clitellum consists of regular flask-like cells; posterior to it again 
the body-wall has assumed its regular appearance. In Deltania Troyeri the elitellar 
thickening stops just before it reaches the papillee, but in Deltania Benhami it stops 
just as it reaches the male pore. The papillee, however, continue to the posterior end 
of the somite. 
The length of the species is about 1 and 14 inch, by ;'; to $ inch wide, taper- 
ing towards the caudal end. In faet the general form and size does not differ from 
the preceding species. In all I found some fifteen specimens, but they were, un- 
fortunately, in poor condition when I arrived home, and the part posterier to the 
clitellum had already begun to decompose. The following account of the anatomy 
is, therefore, not as full as desirable, but enough is known to perfeetly characterize 
