NEW SPECIES OF OCNERODRILUS. 25 1 



Ocnerodrilus sonorae, w.5/. Fig. 57, 58, 59, 60,71, 73, 75. 



This species comes nearest Ocnerodrilus Beddardi., 

 guatemalcp and Hendriei. Some ten specimens collected 

 agreed in the following characteristics : 



The septal gland in somite v is of almost the same 

 size as the one in somite vi and this one again is only 

 little larger than the one in vii. The septal gland in 

 somite viii is higher than in O. Beddardi and is only 

 little smaller than the gland in somite vii. All the 

 glands are less lobed than in O. Beddardi. 



The s-perniatheca (fig. 71, spt/i.), is of about one-half 

 the size as in O. Beddardi, almost bag-like, very much 

 flattened and with no trace of diverticula. There is no 

 differentiated muscular part of the lower portion of the 

 organ, the whole being of the same structure. The 

 spermatheca is about as long as the diverticulum is wide. 

 It is very transparent, and shows much smaller and more 

 irregular cells than the same organ of O. Beddardi. 



The sperm-sac (fig. 71, 5. 5.), in somite ix is large 

 and somewhat lobed. The sperm-sac in somite x is the 

 smallest of the four. The one in xi is larger, but not as 

 large as the one in ix. The sperm-sac in somite xii is 

 very large, much larger than the others. It is lobed and 

 fills the whole of the somite. In no other species is the 

 sperm-sac in somite xii of such size ; the size appears to 

 be constant. 



The sperm duct has no enlargement at the male pore. 



Th.Q prostate is short as in O. Beddardi, but it is more 

 cylindrical and the muscular part is not tapering toward 

 the glandular part, but on the contrary the prostate is 

 gradually increasing in size from the inner apex towards 

 the male pore, and the muscular part is in no way differ- 

 entiated as regard outline. This I consider a good 

 species characteristic of small variability. The prostate is 



