NOTES ON THE STEUCTURE OF OIKOPLEURA. 45 



a. anus, app. appendage or tail, d.t. dorsal ciliated 

 funnel, ec. ectoderm, ep.p. epipharyngeal ciliated groove, 

 671. endostyle, gl. glandular cells in left side (cardiac sac) 

 of stomach, //. heart, hy.p. hypopharyngeal ciliated ridge 

 or groove, i. intestine, ??l mouth, mes. connective tissue, 

 n. caudal nerve (posterior part of myelon), n.ch. notochord 

 (urochord). n.s. nervous system (cerebral ganglion and 

 anterior part of myelon, oes. oesophagus, ov. ovary, o.g. oral 

 glands, o.c. otocyst, o.d. oviduct, jj>A. pharynx, (branchial 

 sac), p.p. peripharyngeal ciliated bands, r. rectum, st. 

 pyloric sac of stomach, st'. cardiac sac, sp. lobes of testis, 

 t. test, sg. stigma leading to atrial pore. 



Plate I. 



Section 8 (from posterior end) showing ovary 

 and lobes of testis. 



Section 22, showing separation off of dorsal lobe 

 of ovary. 



Section 35, immediately behind the alimentary 

 canal. 



Small part of ovary from last section more highly 

 magnified (X 600). 



Small part of testis from last section highly mag- 

 nified (X 600). 



Section 48, showing posterior end of stomach. 



Section 54, showing stomach and oesophagus. 



A part of surface of section 54 more highly mag- 

 nified (X 600). 



Section 61, showing parts of alimentary canal, 

 and nerves. 



Section 71, showing oesophagus opening into 

 stomach. 



