384 EDWARD S. MORSE ON 



PLATE 55. 



Nephridia of various forms. 

 Fig. 1. Right m j ]iliri(liuui of L mint inn. 



Fig. 2. Greatly enlarged view of nephrostome from below, showing lacunae, idem. 

 Fig. 3. Left nephridium of D. lamellima. 



Figs. 4 and 5. Anterior coelomie wall showing terminal portion of nephridial lubes and their external openings, Idem 

 Fig. 4. From outside. 

 Fig. 5. From inside. 



Fig. (i. Nephridia from very young J). lainelluna. 

 Fig. 7. Nephridia in situ of T. eurettiiira. 



Fig. 8. Dorsal section of T. cureanicu, showing position of nephridia in relation to other parts and their slit-like openings 

 outside. 



Fig. 9. Nephridium of T. corcnnicn. 



Figs. 10 and 11. Nephridia of //. psittacea, showing genital band with accessory vesicle, etc. 



Fig. lOa. Enlarged view of bonier of nephrostome, idem. 



Fig. lla. A sinus from body of nephridium greatly enlarged, iil< in. 



PLATE r.(i. 



Nephridia of Terebrululimi. xfjitnitriunalis and Dallina graijii. 

 Fig. 1 to 7. Terebnitulimt septentrlonalis. 



Fig. 1. Left nephridium. 



Fig. 2. Right nephridium with divaricator muscles, segment of intestine, ilio-parietal band, etc. 



Fig. 2a. Nephrostome papillae. 



Figs. 26 and 2c. Appearance of surface of nephridium. 



Fig. 3. Nephridium, with genital band, accessory vesicle, etc. 



Fig. 4. Peduncular end of young specimen showing nephridia. 



Fig. 5. Very young specimen showing nephridia. 



Fig. 5a. Nephridium greatly enlarged. 



Fig. G. External opening of nephridium, front view. 



Fig. 7. Side view of nephridial opening showing nipple-like form. 



Fig. 8. Nephridia of Dallina grayii. 



Fig. 9. Nephridium of last, showing more clearly the erenulated character of nephrostome. 



PLATE 57. 



Genital products, etc., of various forms. 

 Fig. 1. Ovaries and stomachal glands of Glottidia. 

 Fig. la. Portion of stomachal glands. 

 Fig. \b. Portion of ovaries. 

 Fig. 2. Mass of spermaries of Glottidia. 

 Fig. 3. Mass of spermaries of L. nnatina. 

 Fig. 4. Mass of eggs of L. lepidula. 

 Fig. 5. Mass of eggs of Glottidia. 

 Fig. 5d and 56. Eggs in various stages. 

 Fig. 6. Eggs of Viscinisca stclla. 



