SYNAPTA VIVIPARA. 



85 



n. Explanation of Plates. 



[All figures excejit 20 and 2y were drawn witli the aid of a camera Incida.] 

 ABBREVIATIONS USED. 



A. — atrium. LGO, 



AE. — anterior enterocoel. LM. • 



AN. — anus. M. — 



AO. — atrial opening. Mes. ■ 



AT. — accessory tentacle. MD. 



BC. — body-cavity. MY. - 



BL. — blastopore. NR. - 



BV. — blood-vessel. 0. — 



CF. — ciliated funnels. OE. - 



CH. — circumoesophageal ring of blood-system. OEN 



CM. — circular muscles of body-wall. FT. 



CR. — calcareous ring. PV. 



CT. — connective tissue. R. — 



Car.R. — cartilaginous ring. RC. 

 Cir.S. — circular sinus formed from the anterior-pmlon- RN. 



gallon of the left coeloni. SC. 



DV. — dorsal vein of blood-system.. SO. ■ 



E. — enterocoel. SI*. 



Ect. — ectoderm. T. — 



Epi. — epithelium. TC- 



Ey. — eyes. TN. - 



GD. — genital duct. TV. - 



GG. — genital gland. V. — 



H. — hydroooel. WP. - 



I. — intestine. WR. 

 LC. — left coelom. 



. — larval glandular organ. 



— longitudinal nuiscles. 

 mouth. 



— mesenchyme. 



— madrepore. 



— mesentery. 



— circumoral nerve-ring, 

 otocysts. 



— oesophagus. 

 . — nerve-band to mouth and oesophagus. 



— primary tentacle. 



— Polian vesicle. 

 rectum. 



— right coelom. 



— radial nerve. 



— stone-canal. 



— secondary outgrowth of tlie hydrocoel. 



— sense-papilla, 

 tentacle, 

 -canal of tentacle. 



— tentacle-nerve. 



— blood-vessel on inner side of tentacular canal, 

 valves. 



— water-pore. 



— water-ring. 



