592 



COLLEGE ZOOLOGY 



reel <x2r 

 rned 



hi 



slip en ** adh 



B 



reel 



atr ~&" ciU 



hi ■alt-g e-ruZ 



Fig. 339. — Diagram of the metamorphosis of the free, tailed larva into 

 the fixed Tunicate. A, stage of free-swimming larva. B, recently fixed larva. 

 C, older fixed stage, atr, atrial cavity; cil.gr. ciliated groove on wall of 

 pharynx; end, endostyle; fit. heart ; med, trunk-ganglion; n.gn, ganglion; 

 nolo, notochord ; or, branchial aperture ; reel, intestine ; sens.ves, sensory 

 vesicle ; stig, gill-slits ; stol, shoot from which buds rise ; t, cast cellulose 

 envelope of tail. (From Davenport, after Seeliger.1 



