ON SOME PLYMOUTH HOLOTHURIANS. 225 



three- or a five-rayed spicule is produced, at other times further sub- 

 division of the branches of the third order occurs, giving rise to bell- 

 shaped spicules slightly different from the usual form ; the normal form 

 is, however, the one described above. 



^^•V C(? K Jrf.-- 



4-" 





Fig. S. — The campanulate surface spicules of C. normani. Drawn from a piece of the 

 skin (mounted whole) of a specimen 13 mm. long to show a series of stages in the 

 development of these spicules and their compact arrangement.* One fully 

 developed spicule is depicted ( x about 300). 



THE SYNONYMY OF C. SAXICOLA BRADY AND 

 ROBERTSON AND OF C. NORMANI PACE. 



It will be evident from the foregoing accounts that the synonymy 

 of the two species mentioned above may be expected to be and actually 

 is in a highly confused state. This confusion has been rendered still 

 worse by the fact that continental zoologists have regarded C. ynontagui 

 as a good species, whereas it has been shown to be a complex one. Thus 

 according as the one or the other constituent of C. montagui has fallen 

 into the hands of these zoologists, the other constituent — on the Continent 

 — has been given another name. There can be little doubt that the two 

 species discussed in this paper do occur on the Continent, but at present 



* Drawings were made of some of these stages of development from the fresh living 

 animal as a safeguard against their possible subsequent alteration in preservation. It 

 was found, however, that the spicules in the mounted specimen agreed with the drawings 

 from the Uving animal. 



