38 CALIFORNIA ACADKMY OF SCIENCES. 



genus, and average about twice or three times as close as in Bcltania Troyt't'i. 

 Tliis is a prominent and constant characteristic. The characteristic feature of the 

 genus, which consists in the narrowing together of the ventral setse 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 seta3 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 settx? exist on both sides of 

 the male i)ore, l)ut it is also seen towards the spermathecal pore, though here in a 

 smaller degree. In Deltania IVoyerl, there is not a trace of such an increased ap- 

 proach of the ventral setre towards the spermathecal pore. Another characteristic as 

 regards the setse 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- 

 thecfe almost touch. 



The spermathecal ]>ore is situated in the intersegmental groove between viii 

 and ix, in front of seta 1. In Dfiltanln Troi/eri, the spermathecal 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 sette, the spermathecse in that species are 

 much further apart, and do not ci'owd the ventral ganglion. Oviducal pore as usual 

 in xiv. Penial setfe on i)apillre in xvii, opening in the male pore. The elitellum 

 comprises three full and wide somites, xiv, xv, xvi, and two smaller ones, xiii and 

 xvii, as in other species. 



The genital region (fig. 48) around the male papilliie is much simpler than in 

 Dellania 7roijeri. The two papdht are situated much closer together, and there are 

 no suctorial depressions with their fan-shaped arrangement of muscles. The penial 

 setfe 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 xviii. These 

 threads, however, exist only in the longitudinal groove between the papilke, all run 

 parallel with each other and with the long axis of the body (fig. 48). As to their 

 nature I am not at all certain. They are apparently too thin to be muscles. The 

 elitellum proper in this as in the preceding species ends at the papillae or male pore. 

 Anterior to it the elitellum consists of regular flask-like cells; posterior to it again 

 the body-wall has assumed its regular appearance. In Deltania IVoi/eri the clitellar 

 thickening stops just before it reaches the papilla, but in Deltania Benhami it stops 

 just as it reaches the male pore. The papillfp, however, continue to the posterior end 

 of the somite. 



The lengtli of the species is about 1 and Ij inch, by yV to ^ inch wide, taper- 

 ing towards the caudal end. In fact the general form antl 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 ])art posterier to the 

 elitellum had already begun to decompose. The following account of the anatomy 

 is, therefoi'e, not as full as desirable, but enough is known to perfect!}' characterize 



