ZOOL.-VOL. II.] EISEN—OLIGOCHMTA. 171 



Diplocardia (Aleodrilus) Keyesi (Eisen). 



Plate XIII, Fig. 136. 



Aleodrilus Keyesi Eisen, Mem. Cal. Acad. Sci., Vol. II, No. 5, 1896. 

 Diplocardia Keyesi Eisen, Zool. Bull., Vol. II, No. 4, 1899. 



Defaiition. — Color, flesh, marbled violet, no pigment. Size, 70 mm. by 5 

 mm. Somites, 150. Prostomium divides somite I about one-half. Dorsal 

 pores, the most anterior one in I, VIII/IX. Spermiducal pores in XXI. 

 Spermathecal pores, two pairs, in VIII and IX, in front of setae ab. Prostate 

 pores in XX and XXII. Oviducal pores in front of setae a. Setae all ventral; 

 a-b slightly larger than c-d; a-a larger than b-c. No sculpture. Penial setae 

 none. Spermathecal setae not differentiated. Clitellum ring-like anteriorly, 

 posteriorly saddle-shaped. Genital zone not distinct; two parallel grooves in 

 }i XX-% XXII; groove almost straight, with a knob at each apex; con- 

 cavity turned ventrally. QEsophagus without calcic concretions. Gizzards in 

 V and VI. Sacculated intestine in XV. Dorsal vessel single, not covered 

 with chloragogen cells. Hearts in X, XI, XII, with large pulsating divisions; 

 no chloragogen cells. Nephridia, meganephridia, no coelomic mantle. Testes 

 in X and XL Sperm-flinnels in X and XI. Sperm-ducts, which join at 

 XII/XIII in a common muscular sheath; fuse in XX/XXI. Sperm-sacs, one 

 pair preseptal in IX, one pair postseptal in XII. Sperm-masses in X and XI. 

 Oviducts in XIV. Prostates confined to one somite each, small, tubular, 

 thicker at apex. Spermathecae, two pairs in VIII and IX; distal end knob- 

 like; the duct is very slender and long, with a minute wart-like and ear- 

 shaped diverticle situated about the middle. 



Septal formula: — 



VI/VII, VII/VIII, VIII/IX, IX/X, X/XI. 



Habitat. — Ensenada de Todos Santos, Baja California, 

 Mexico. 



Detailed Description. 



SpermatheccB. — (fig. 136). The form of the spermathecae 

 is the same as was figured in a previous paper (Eisen 18). 

 The duct is very long and slender, though confined to one 

 somite. It carries a small wart-like and ear-shaped diverti- 

 cle, situated about half-way from the globular knob to the 

 base. In this respect the species agrees with the other 

 known species of the genus. The diverticle is no wider 

 than the duct and resembles an agglomeration of three or 

 four minute warty protuberances. In the former paper 

 these protuberances were noted but were then considered 

 accidental. I am now satisfied that they constitute a true 



