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



half that between the corresponding setae in somite IX. 

 Setse c and d are as a rule absent in the clitellum. The 

 common set^ are faintly ornamented with six or eight 

 rows of short transverse wavey lines running obliquely 

 across the seta from apex to center. 



Penial Setce. — The penial setas are slightly sigmoid at 

 the very apex. The one I dissected was smooth except for 

 two or three deep creases in the concave part just below 

 the apex, but I am not certain whether these creases were 

 natural or accidental. 



Sef>ta. — The septa are all narrow and those thickened 

 are only slightly so. 



Intestine. — The pharynx is developed only dorsally; it 

 forms a deep fold or sinus. 



The gizzard in V is very rudimentary, the thickened 

 muscular layer being not more than twice as thick as the 

 same muscular layer in the following somites. It does not 

 cause the least swelling of the intestine in somite V, and is 

 hardly noticeable. The tubular part of the intestine is very 

 straight and only slightly nipped by the septa. This part of 

 the intestine is ciliated in somite XVI and in the posterior 

 part of XV. In XVI it connects with the sacculated intes- 

 tine which begins in XVI. The intestine is covered with 

 small chloragogen cells in XV to XXIV. 



Sexual Organs. — These offer few characteristics. There 

 are two pairs of testes, two pairs of sperm-sacs, and one pair 

 of short ovisacs in XIV, projecting from the anterior septum 

 backwards. 



The sperm-ducts run singly until they join the prostate at 

 a point just before it enters the body-wall; therefore the- 

 ducts actually enter the prostate. The prostate consists of 

 a glandular and a muscular part, the former being from three 

 to four times as wide as the latter, which equals it in length, 

 or maybe even longer. In one specimen the muscular part 

 is half as long again as the glandular; in another they are 

 of about the same length. The glandular part consists of 



