4S(> 



ZOOLOCY 



SECT. 



which is separated by spaces into a series of parallel bands. 



Between the bundles of the longitudinal 

 l en l layer of muscle runs a system of canals 



which communicate with the body- 

 cavity by transverse branches. 



There is a spacious coelome, but it 

 is traversed in all directions by fila- 

 ments and strands of connective-tissue, 

 -ocs with which are mixed very fine muscular 

 fibres ; these mostly run from the wall 

 of the body to the alimentary canal. 

 lav,.- F^T, \|\l Floating in the coelomic fluid are (1) 



nraftuHU colourless amoeboid corpuscles ; (2) 



M'i rounded biconcave corpuscles, faintly 



dorf.refr-iS^iK& ~rec coloured by a substance, hamerythrin, 



can. f> cfb 



m.n.co 



n. co- 



retr- 



'n. m/js rtt 



IG. 4(15. Dissection of the internal or- 

 gans of Sipunculus nudus. i/orx. retr. 

 dorsal n-tractor muscles of the intro- 

 vert ; int. intestine ; /. n. ci>. muscles 

 accompanying the, nerve-cord ; n. /<>. 

 nerve-cord ; ni'i>h. nephridiuiu ; <BS. 

 oesopliagns ; reel, rectum ; lent, tenta- 

 cular fold. (After Vogt and Jung.) 



Fit). 404. Anterior part of the nervous syMem 

 of Sipunculus nudus. ran. <>. cell, cere- 

 bral organ ; conns, os, cesophageal connective; 

 . ii/n. />'/. nerves to retractor muscles ; . */il, 

 splanchnic nerves ; it. In. I I, nerves to ten- 

 tacular fold : /, //, nerves from ventral cord ; 

 24, main mass of brain. (After Ward.) 



