Geodia agassizii Lendenfeld, (young) from Station 4228. 



Figures 1-14. 



1-8. — Four stages of development of the sterraster; magnified 1800; u. v. phot. Zei.ss, q. monochr. 1.7, 

 q. DC. 10: 



1, 3, 5, 7, the highest part of the upper surface in focus; 



2, 4, 6, 8, the sterrasters (parts of sterrasters) represented to the left of them in Figs. 1, 3, 5. 7, 



focused lower; 



1, 2, young sterrast«r 17 fi in diameter; 

 3, 4, young sterraster 23 fi in diameter; 

 5. 6, young sterraster 50 /i in diameter; 

 7, 8, young sterraster 70 p. in diameter. 

 9-14. — Paits of the turfare of adult sterrasters and sterroids; magnified 1800; u. v. phot. Zeiss, q. 

 monochr. 1.7, q. oc. 10: 



9, 14, part of the surface oppo.site the umbilicus of sterroids with distant protruding rays the 



spines of which are rough, apparently covered with secondary spinelets; 



10, umbilical part of the surface of a sterraster with extremely thick rays the spines of which are 



numerous and smooth; 



11, part of the lateral surface of a sterroid; 



12, 13, part of the surface, some distance from the umbilicus, of a sterraster with thin protruding rays 



standing verj' close together; 



12, focused lower; 13, focused higher. 



