SYM PAGELLA ANOMALA. 105 



canalaria seem also to pass hy gradations insensibly into the 

 smaller parenchymal oxyhexactins, there being such forms as 

 stand between the two in respect of both the situation and the 

 characters of rays. — The canalaria occur at places in tolerable 

 abundance, placed side by side in irregular disposition but always 

 with one ray freely projecting into the canalar lumen. At other 

 places they are found only in scattered distribution. The incurrent 

 canals seem to be totally wanting in s[)ecialized canalaria of 

 the kind. 



The hexasters of the species consist of the strobiloplumicome 

 and a peculiar onychaster-like kind of discohexasters, leaving out 

 of account all those which occur but inconstantly or which in 

 their distribution are confined to the stalk. 



The ony chaster -like liexastcrs (figs. 12-15) occur in the 

 choanosomo, not very abundantly but still in moderate frequency. 

 They are slender-rayed and rather small, measuring 68-100/^ in 

 diameter. Each short jDrincipal bears 2 or 3, sometimes 4, widely 

 divergent, nearly straight or slightly bent terminals, which are 

 thickest at base and thin out to a very fine caliber towards the 

 end. They are obsoletely rough-surfaced or nearly smooth. 

 Occasionally the rosette is hemihexactinose (fig. 13). Now the 

 very terminal point of the terminals is without a trace of a disc- 

 like expansion but bears a whorl of 3-6, sometimes only 2, short 

 and exceedingly fine prongs or branchlets, not more than 4 /^ 

 long. Unlike the claws in a true onychaster the terminal branch- 

 lets are straio;ht — not recurved — and are directed sometimes nearlv 

 transversely, but generally obliquely forwards and outwards, so 

 as to form a strongly divergent fork or umbel (fig. 15). The 

 branchlets easily fall off, and then, as also when they are over- 



