8 PROCEEDINGS OF THE NATION^AL MUSEUM vol.76 



R. haeuUfer F. E. Schulze (1904, p. 34), South Africa. Autoder- 

 malia, diacts 200/x to 600/^ long. Autogastralia, diacts commonly 

 longer than the autodermalia. Oxyhexasters 100/x to 160ju, diameter ; 

 principal rays very short, often vestigial. Discoctasters IQOfi diam- 

 eter. Schulze regards this species as very close to the preceding. 

 He looks on the presence of only one form of discoctaster as the most 

 important differential. 



B. australis Topsent (1901, p. 37; Ijima 1904, p. 237), Antarctic. 

 Autodermalia predominantly diacts but stauracts and pentacts also 

 abundant. Autogastralia, hexacts, all rays similar. Paratangential 

 rays of hypodermal pentacts shagreened (that is, finely tuberculate) 

 and also with spines. Oxyhexasters 140/a to 160/a diameter. Discoc- 

 tasters ISOju, diameter; terminals few, three rarely four. Microdis- 

 cohexasters not observed. 



R. roeperi F. E. Schulze (1887, p. 158), having hypodermal pen- 

 tacts with spineless paratangential rays, was transferred by Ijima 

 (1897, p. 55) to Staurocalyptus Ijima (1897). Likewise R. dowlingii 

 L. M. Lambe (1893, p. 37) from British Columbia was transferred to 

 Stawrocalyptv^ by Ijima (1897, p. 53). 



It will be seen from this survey that ten of the thirteen known 

 species of the genus occur on the two sides of the North Pacific, the 

 coasts of Alaska, British Columbia, and California on the East, the 

 coast of Japan on the West. The variety here recorded is the only 

 form in which the free ray of the autogastral hexact spicule is known 

 to be smoother and smaller than the other rays, although one would 

 expect to find in R. asper (see above) spicules of this kind. The op- 

 posite development, leading to a free ray longer and more spinose 

 than the others, has occurred in a number of forms (seven). In a 

 few forms all six rays are similar. In two the hexacts have degen- 

 erated to diacts. 



REFERENCES 

 Ijima, 1. 



1897. Revision of Hexactinellids with Discoctasters, with Descriptions of 



Five New Species. Annotationes Zoologieae Japonenses, vol, 1, parts 

 1 and 2. Tokyo. 



1898. The Genera and Species of Rossellidae. Annotationes Zoologieae Ja- 



ponenses, vol. 2, part 2. Tokyo. 



1904. Studies on the Hesactinellida. Contribution IV. Rossellidae. (Im- 

 portant for the genera.) The Journal of the College of Science, 

 Imperial University of Tokyo, vol. 18, article 7. Tokyo. 



1927. The Hexactinellida of the Siboga Expedition. Siboga-Expeditie, 

 Monographe VI. Brill, Leiden. 



KiBKPATBICK, R. 



1901. Description of a new Hexactinellid Sponge from S. Africa. Annals 



and Magazine of Natural History, ser. 7, vol. 7. London. 



1902. Descriptions of South African Sponges. Marine Investigations in 



South Africa. Department of Agriculture. Cape of Good Hope. 

 Capetown. 



