62 THE WHENCE AND THE WHITHER OF MAN 



bands of longitudinal mus- 

 cles. These latter have been 

 grouped in the four quad- 

 rants, a much more effective 

 arrangement than the cyl- 

 indrical layer of the sche- 

 matic worm. Furthermore, 

 the animal has on each 

 segment a pair of fin-like 

 projections, stiffened with 

 bristles, the parapodia. 

 These are moved by special 

 muscles and form effective 

 organs of creeping. 



Within the muscles is the 

 perivisceral cavity, and in its 

 central axis the intestine, 

 segmented like the body- 

 wall. The reproductive 

 organs are formed from 

 patches of the lining of the 

 perivisceral cavity, and the 

 reproductive elements, when 

 fully developed, fall into the 

 perivisceral fluid and are 

 carried out by nephridia, 

 just such as we found in the 

 schematic worm. Beside 

 the perivisceral cavity and 

 its fluid there is a special 

 circulatory system. This 

 consists mainly of one long tube above the intestine 

 and a second below, with often several smaller parallel 



7. EUNICE LIMOSA (ANNELID). LANG, 

 FROM EHLERS. 



Front and hind end seen from dorsal 



surface. 



/. fP> fc, feelers ; a, eye ; k, gill ; p, 

 parapodia ; ac, anal cirri. 



