STRUCTURE OF TWO NEW GENERA OF EARTHWORMS. 239 



There is a median aperture (as inTeleudrilus and other 

 Eudrilidse) of the ''prostate glands" upon the 17th segment; 

 this is spoken of as a slit-like orifice ; but the apparent 

 difference in this particular from Hyperiodrilus africanus 

 may be a mere question of the state of contraction of the 

 worm^s body. From the aperture upon the 17th segment a 

 deep furrow runs forward to a process which bears the outlet 

 of a peculiar gland ; this process is median, but slightly in- 

 clined to the right side. This papilla, however^ appears from 

 Michaelsen's description to lie upon the 13th segment, near to 

 the ventral unpaired orifice of the spermatheca. As already 

 mentioned, the lateral processes, though varying somewhat in 

 their position upon the segment, are always on Segment 17. 



On the 13th segment is a median aperture (see fig. 24) 

 corresponding to the male generative orifice upon the 18th 

 segment, though situated at about the middle of the segment, 

 rather nearer to the anterior than to the posterior bouudary. 

 This aperture was not at all conspicuous upon any of the 

 specimens examined, and might very easily be overlooked. 



§ Integument. 



The layers of the body-wall are as in other earthworms, 

 except for the presence in the epidermis of certain peculiar 

 organs, which appear to be met with in all Eudrilidse except 

 Nemertodrilus ; but this genus is in other respects (seep. 

 266) a very aberrant member of the family. These structures 

 are described later. 



The muscular layers of the body-wall show no noteworthy 

 peculiarities as regards the structure and arrangement of the 

 fibres. The longitudinal coat does not exhibit the bipinnate 

 character which is frequently met with in earthworms, par- 

 ticularly in the Lumbricidse. 



The muscular coats contain numerous irregular spaces 

 filled with coelomic corpuscles (see fig. 3) ; besides the ordinary 

 corpuscles large multinucleate bodies are met with, which 

 may be pathological formations. I believe that Kiihenthal 

 (13) was the first to specially call attention to the spaces 



VOL. XXXII, PART II. — NEW SEE. y 



