360 



NEMATHELMIS THES. 



layer of the integument lies a complicated system of canals, filled with 

 a clear fluid containing granules. Beneath the internal layer of the 

 integument, which layer is often very extensive and of a yellow 

 colour, is placed the powerful muscular tunic; it is composed of 

 external transverse and internal longitudinal fibres, and bounds the 

 body cavity. Tae complicated ramified system of dermal canals, of 



which two principal longitu- 

 dinal trunks may be recog- 

 nised, is filled with juices, 



and probably functions as a 



nutritive apparatus. The 



portion of this system which 



extends into two bodies (the 



lemnisci, fig. 289, Le) project- 

 ing behind the proboscis 



through the muscular tunic 



into the body cavity, probably 



acts as an excretory organ, 



since the contents of the fre- 

 quently anastomising canals 



of these lemnisci is usually 



of a brown colour, and consists 



of a cellular mass rich in 



concretions. According to 



Schneider, the vessels of the 



lemnisci open into a circular 



vessel in the integument, and 



only communicate with the 



network of canals in the 



cephalic region, while the 



other dermal vessels (nutritive 



FIG. 290. Male of EcU- 



norhyncu, angustatu* apparatus), the Contents Of FlG - 291. - Generative 



(after R. Leuckart). w hiVh difFpr* from that of thp ^ & ^ f female 

 S proboscis Its J&chinorhynchus gigas 



sheath of the probos! vesselsof the lemnisci, are com- ^'^j. ^^^^ 

 cis; Li, ligament; p l e telv shut off from the latter. sSSdfloccuil. F**F 



Or, ganglion ; Le, lem- 



The 



nisei; T, testes; rd, Generative organs. The ^e^rTutems T 



proL d tic fer sacs a; Be' bod y Cavit ^ through which vajna ;' S, Patera! 



ductus ejacuiatorius ; fluids circulate encloses the 



B, retracted greatly developed generative 



pouches of the bell ; 

 Gd, dorsal cells at the 



base of the bell; (?/, 



lateral cells. 



, . , , , 



organs, which are attached 

 to the end of the sheath of the proboscis by a ligament (figs. 290 



