Fig. 8. A tube isolated and viewed from the lower side. Y, bud at- 

 tached to the upper endocyst ; X, young, fixed statoblast attached to the 

 lower endocyst ; Q, ccenoecial walls ; Q, base of membranous ridge ; E, en- 

 docyst. 



Fig. 9. Two figures of the same statoblast, showing the variations in 

 the form and position of the vacant spot in the statoblast of fig. 8. 



Fig. 10. View of the same from the upper side, showing the membra- 

 nous ridge crossing the statoblast and apparently connecting with the endo- 

 cyst on the upper side. 



. Fig. 11. An older specimen, in which the ridge has formed a tube. 



Fig. 12. A still older specimen, from the interior of the ccenoecium, 

 showing the elliptical depression in the horny sheath. 



Fig. 13. View of the lophophore from above, with the tentacles and 

 calyx removed, showing the distribution of the nerves. H, bases of the ten- 

 tacles ; G, calyx ; M, lophophoric flexor ; U, lophophoric nerve branches ; 

 U ', tentacular nerve branches ; I ', epistome ; I", mouth. 



Fig. 14. Epistome isolated and viewed from above, showing the mus- 

 cles. P, median muscle ; P ', lateral muscles. 



Fig. 15. Lateral view of a portion of the interior of one arm with the 

 lophophore removed, showing the outer and inner tentacular bands, and the 

 membranes of the endocyst in an alcoholic specimen. O, outer tentacular 

 bands ; O ', inner tentacular bands. 



Fig. 16. Direct and profile views of a group of cells from the first mem- 

 brane of the coencecial endocyst of fig. 2. 



PLATE 14. 



CRISTATELLA OPHIDIOIDBA Hyatt. 



Fig. 1. Magnified view of an adult polypide in its cell. E, endocyst; 

 Q, muscular walls of the cell ; M, gastric retractors ; M r , lophophoric re- 

 tractors ; M ", brachial retractors ; N, anterior retentors ; Z, clear spaces 

 in the endocyst between* the bases of the outer tentacular bands ; O, bases 

 of outer tentacular bands. 



Figs. 2, 3, 4. Upper and lower side, and profile view of statoblast. 

 W, horny sheath; W", annular sheath ; W" f , spines. Of the last, there 

 are in nature twenty-two short, and thirty-two long ones. 



Fig. 5. View of the anus, showing its oblate form, and also the great 

 breadth of the intestine, when compared with the oesophagus and the upper 

 part of the stomach in the back ground ; K, oesophagus ; K ', stomach ; 

 K", intestine ; K, anus. 



Fig. 6. Section of stomach, showing the hepatic folds. J, hepatic 

 folds. 



Fig. 7. Oblique view of the tip of a tentacle, showing the fan-shaped 

 attachments of the tentacular bands. 



