236 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



setae. Sperm-ducts straight, joining in XVII, opening into the interseg- 

 mental groove between XVII and XVIII. Prostates, two pairs; the anterior 

 pair opens immediately ventral to the sperm-ducts in XVII, the posterior 

 pair opens in the center of XIX. Spermathecae, two pairs; one pair in VIII, 

 one pair in IX, their pores in line with setae ab in the intersegmental grooves 

 between VII/VIII, VIII/IX; several diverticles near the base. Oviducts sep- 

 arate. Sacculated intestine commences in XIX. No typhlosole. No intestinal 

 coeca. Gizzards, two in V and VI. Calciferous diverticles. three pairs in 

 XV, XVI, XVII, opening into the intestine through three pairs of pores. 

 Last hearts in XIII. Nephridia are micronephridia, ten on each side, each 

 one with a coelomic mantle. Testes and sperm-funnels in X and XL Ovaries 

 in XIII. Color reddish brown, pigmented, strongly iridescent on dorsal 

 side. 

 The following septa are thickened: — 



VIII/IX, IX/X, X/XI, XI/XII, XII/XIII, XIII/XIV, XIV/XV. 



Habitat. — City of Mexico, Mexico. Collected by Pro- 

 fessor Albert Koebele, September, 1897. Five specimens 

 preserved in formalin, only three of which possess an exte- 

 rior genital zone. The clitellum is not differentiated in any 

 of the specimens. 



Every species of this interesting genus proves conclu- 

 sively that the genus cannot be far removed from Benhamia, 

 and that with Michaelsen we must consider Dichogaster as a 

 reduced Benhamia. The present species demonstrates also 

 that this genus is not as incongruous as Beddard supposes, 

 and that the species with separate prostates posterior to the 

 male pores are not sufficiently distinct to warrant assigning 

 them to a separate genus. In the species under consideration 

 one pair of accessory prostates is found in XIX, making 

 the species intermediate between those species without 

 accessory prostates and those with three accessory pairs 

 (Z?. Damonis and D. Townsendi) . 



Detailed Description. 



The -prostoTniuTn is exceedingly narrow, the posterior pro- 

 jection being merely a furrow completely dividing somite I. 

 The somites offer nothing especially characteristic. The 

 clitellum is not developed in any of the five specimens, but 

 there is no reason to suppose that it is wanting in fully 

 mature individuals. 



