108 



TUNICATA. 



Order 1. DESMOMYARIA (SALP.E). 



Thaliacea of cylindrical, usually dorso-ventrally flattened form, with 

 band-shaped muscular hoops arid thick mantle (fig. 566). The 



c 



N 



M 



FIG. 568. The forms of Dnlioltuit ilfntifuloti'm (", h, '', ', after C. Grobben ; c, after Gegenbaur)- 

 a, Sexual auimal. 0, Mouth; A, cloaca] aperture; Kl, cloacal space; S, nerve centre: 

 //.<, cutaneous sense organ ; Wi>, arch of cilia ; ]!'</, ciliated pit ; Eifl, endostyle ; Br, gills : 

 C, heart ; D, intestine ; T, testis ; Oc, ovary ; M, muscular hoops. /;, First asexual 

 generation. ,S'/c, Ventral stolc.m ; xt<l, dorsal stolon; Ot, auditory organ, c, A later stage 

 of b, with developed dorsal stolon and aborted intestine and gills, less highly magnified. 

 Ms, Median buds ; Is, lateral buds, d, Nutritive animal produced from the lateral buds 

 with large mouth and without cloaca ; 0< , "-upli.-L^us. e, DoHuluiii larva with larval tail : 

 Cli, chorda (uroclionl). 



anterior opening is furnished with a valve-like lip which can be shut 

 down. The gill reaches from the ganglion to the oral region, and in 

 consequence of the development of two large lateral branchial slits 



