﻿THE 



CANADIAN^ EECOED 



OF SCIEl^CE. 



VOL. VII. JULY, 1897. No. 7. 



Postscript to a " Description of a New Genus and 

 Species of Cystideans from the Trenton lime- 

 stone AT Ottawa." 



By J. F. Whiteaves. 



In the January number of this journal for the current 

 year the writer endeavoured to describe a new genus and 

 species of blastoid-like cystideans from the Trenton 

 limestone at Ottawa, under the name Astrocystites Cana- 

 densis. Since this description was published, the writer 

 has been informed by Mr. F. A. Bather, M.A., of the 

 Natural History Department of the British Museum, that 

 Haeckel in 1896 separated Astcrohlastus tuber culatus, 

 Schmidt, from the typical A. stellatus of Eichwald, under 

 the new generic name Asterocystis. Mr. Bather thinks 

 that there is not sufficient difference between the words 

 Astrocystites and Astrocystis, and it would obviously be 

 inconvenient to use such essentially similar names for 

 two such closely related genera. The writer, therefore, 

 desires to be allowed to substitute the generic name 

 StegctnoUastus (from GTeydvog, closely covered, with 

 reference to the large covering plates and covered mouth, 

 as kindly suggested by Mr. Bather) for that of Astrocystites, 



27 



