THE fJErUVREA OF .TATAX. 



79 



II, 2 nitraetor innsclcs. 



f(, — Hooks provitU'd with one apical tooth. Dorsal vessel 



devoid of contractile villi 7'. nahuouHc. P. 20. 



ft. —Hooks wantiii'j;'. Papillae prominent. f 'Ontractile 



villi numerous and ramified 



T. oiiomichinjium. P. 2(!. 



SIPUNCÜLÜS. 



j^,_Tentacles flap-like. The chitin over the body proper folded 

 into rectangular areas. Introvert with very tall, posteriorly 

 directed papilla>. Longitudinal muscle separated into ?>\ 



Imndles '^'- i""^"^-- I'- •>'• 



B.— Tentacles filamentous. Body-surface shows no rectangular 

 areas. Introvert and body proper covered with skin-bodies. 

 «7.— Longitudinal muscles 18-21. Crescent-shaped dis- 

 sepiments on the inner side of the body-wall. With 

 a bifurcated fixing muscle.... 6'. cumanensis. P. 32. 

 /,. —Longitudinal muscles 15. Devoid of crescent-shaped 



dissepiments. Fixing muscles 2 



,S'. (irnii niicn^i-'i. P. 3S. 



PHASCOLOBOMA. 



I. 2 retractor muscles. 



No hook. Introvert long. Body as a whole coiled 

 into a spiral P- nif/mm. P. 'X 



II. 4 retractor muscles. 



^,__With hooks and 1-2 fixing muscles. 



a, Hooks provided with 4-5 small accessory teeth and 



arranged in ring-rows. A single fixing muscle. 

 Segmental organs consist of two elongate lobes 



directed oppositely P. mhal-ianum. P. 7. 



/;. A somewhat larger form. Hnoks dispersed, almost 



straidit, and devoid of accessory teeth. 2 fixing 

 muscles. Segmental organs of an ordinary shape.... 



7^. (wsfoiii. P. 12. 



