THE ANATOMY OF ONCHOLAIMUS VULGARIS, BAST. 105 



In prepared specimens the hairs are very frequently broken 

 off. 



The cuticle is also perforated by the openings of the 

 ventral and tail glands (PI. 7, fig. 5, ig-f^l^-) and of the glands 

 of the lateral lines. 



From the base of the lips four flattened pouches (PI. 7, 

 fig. 2, e) extend outward and backward in the substance of 

 the cuticle as far as the oral circlet of hairs. They are semi- 

 circular in shape, the base directed toward the mouth, the 

 arc away from it. At the base of the lips the pouches are 

 continuous with each other, and here the four pore-like open- 

 ings to the exterior are situated. 



The pouches contain a number of coarse granules with 

 amphophil staining reaction. I have not been able to trace 

 aiiy connection between these granules and the epidermal 

 protoplasm. 



From the nature of the contents I believe the function of 

 these structures to be glandular. They appear to correspond, 

 not with the " Seitenorgane" of other forms, but with the 

 circumoral ^'patterns" and glands described by De Man in 

 0. fuscus (12). 



The Epidermis and Nervous System. 



It is hardly possible to separate these two. The only 

 structure which is definitely specialised as nervous is the 

 circuuKDesophageal ring; other structures which are nervous 

 in function, such as the ganglionic mass which surrounds the 

 ring and the anal ganglion, shade off into the general 

 epidermis. I shall, however, describe the latter first. 



The epidermis consists of four lines of cells — the longi- 

 tudinal lines (Pi. 7, fig. 3, mdl, mvl, ll), which run from one 

 end of the body to the other, and which project into and 

 divide the muscular layer of the body wall, and of a thin 

 layer of protoplasm — the subcuticula or hypodermis (PI. 7, 

 fig. 3, sc), which connects these four lines, and lies between 

 the cuticle and the muscular layer. This consists merely of 



