(5) 



did the diatoms keep the water from bocomi-a,, polluted bwt they 

 also afforded abundant food for the Pnorcnis so tiriat healthy in- 

 diviauals v.-ith their lophophcral tentacles fully expanded v;ere 

 continually at haiid f o r a live study. The author is much in- 

 debted to Dr. Caswell Grave, the originator of the diatom meth- 

 od in rearing Echinoderm larvae, for the use of his aquaria. 

 Drew's modification of Patton's method for imbedding and oriont- 

 ing f^SES was used with fairly i.,ood success, althougir; a large per- 

 centage of the embryos were broken durin^^ the process. Most 

 of the em.bryos were cut into y'^ctions thre^yO thick but for 

 so0ie points sections two yO' ti.ick were used, 

 Br e e d i 'i^i^ ^ Habits. _ 



^aidrews's (1) observations on Phorcnis architecta bring him 

 to the concliisicn that either the sexes are separate in ti.at 

 species or that if the individuoils are hermapiirodi ti c the male 

 and female elements mature at different times. I lictve exam- 

 ined many specimens during May, June, July, August, Septej;iber 

 and October, both by ineans vV sections ana wl:en alive. During 

 this time in no case have 1 found ovaries arid testes occurring 

 at the same time in an individual. There is no doubt ,ho wever , 

 but vvhat ovaries and testes occur together in the same individ- 

 ual in P. ^ustralis. Benhain (ir) has observea this, as I have 

 also in material sent to me by Mr. Ikeaa. 



