74 



EISEN 



MICHAELSENA PAUCISPINA sp. nov. 

 Text-fig. 43. 



Definition. — Length 7 mm., width .2 mm. Somites 45. Seta3 

 absent in somites I to III ; in somites IV to XIII no lateral setae 

 present, but each of these somites, except VIII and XII, possesses two 

 ventrally located setae, each corresponding to the ventral fascicles. 

 Commencing with somite XIV, all the posterior somites contain 4 

 sets each, each seta corresponding to a ventral or lateral fascicle. In 



the last quarter of the body the setae 

 gradually increase in size in such a 

 manner that the setae in the last ten 

 somites are twice as thick and a trifle 

 longer than the anterior setJE. Setae 

 are straight, pointed with a swelling 

 at the center. Prostomium large, 

 rounded. Head-pore small, between 

 prostomium and I. Septal glands 

 in IV to VII. Dorsal vessel seems 

 to rise in XV. Clitellum distinct, 

 in XII and XIII. No sexual papillae. 

 Color pale yellow. 



Locality. — Santa Barbara, Cali- 

 fornia (seashore). Prof. H. P. John- 

 son of the University of California. 

 A single specimen, preserved on a 

 microscopical slide. 

 Characteristics. — The nature of the single specimen did not 

 allow any dissection, and it was thought best not to attempt sectioning. 

 This explains the want of knowledge of any of the interior structures. 

 The species differs from M. fuonochceta Michaelsen by its lighter color 

 and by the absence of lateral set£e in the somites anterior to clitellum. 

 The two species are, however, most closely related. 



Spe7-mathecce. — Judging alone from optical view of the body, the 

 spermatheca appears to possess a long narrow duct, at the base of 

 which are a few glands. The ampulla seems to be very large and 

 deltoid, projecting downward somewhat in the manner represented in 

 the figure. No other details can be added. 



Subfamily L UMBRICILLIN^^. 



With the exception of Stercutus and Bucholzia the structure of the 

 penial bulb is rather uniform and varies but little in the various genera. 



Fig. 43. MichaeUena paucispina. 



