VOL. II.] Anatomical Notes on Stitroa Alpcstris. 323 



pearance. The discovery of a new one is the more interesting, as 

 only one well defined species of Rhynchelniis* has been described, 

 although it is probable that a closer examination of this annelid will 

 increase the number. 



SuTROA Eisen. 



Prostomium filiform. The spermathecae consist oi several pairs 

 or lobes all opening into a central receptacle or atrium situated in 

 somite VII. One or more pairs of albumen glands. 



Rhvnchelmis Hofifm. 



Prostomium filiform. One pair of spermathecse, each receptacle 

 opening separately in somite VIII. One central albumen gland. 



From the above description of the two genera it will be seen that 

 the principal characteristic of Sutroa is the absence of a central 

 albumen gland, and the centralization of the seminal receptacles or 

 spermathecae which open into a common and central atrium or 

 receptacle. 



Of the genus there are now known two species. 



Sutroa rostrata Eisen. The ventral vessel is forked in 

 somite VIII. The two forks being connected by a secondary vessel 

 in each somite. The ventral vessel is only connected with the dorsal 

 vessel in the cephalic lobe. The spermathecal atrium opens in somite 

 VIII; albumen glands in somites IX and X; spermiducal pores be- 

 tween somites X and XI; oviduct between XI and XII. Sperm-sacs 

 begin in XV and extend towards XXIV or further. Testes in X, 

 ovary probably in somite XXXII or in its vicinity. Egg capsule 

 oblong, not pointed. Habitat: Mountain Lake, at Marine Hos- 

 pital, San Francisco; elevation 40 or 50 feet above the ocean. 



Sutroa alpestris n, sp. Ventral vessel forked in sumite V, 

 each fork being connected with the dorsal vessel by one perigastric 

 secondary vessel in each somite. The ventral vessel is connected 

 with the dorsal vessel in the majority of the somites by two pairs 

 of feathered secondary vessels. The spermathecal atrium opens 

 in somite VII; albumen glands in VIII and IX; spermiducal 

 pores open in somite IX; oviduct between somites X and XI; 



^ rr 



Vejdovsky: Anatomische Stiulien, Rhynchelmis, Zeitschrift f. w. Zool. Bd. xxvii, 

 Taf. xxi-xxiv. 



