116 MR FORBES ON THE ASTERIAD^fc 01*' 



ral views, and excellent generic characters may be derived 

 from the disposition and structure of the spines and suck- 

 ers, more permanent than those derived merely from the 

 general form of the animal. In only one instance do I 

 find myself obliged to differ from IVL Agassiz ; the grounds 

 of that difference are, however, such as I feel confident 

 the learned professor will himself admit. I allude to my 

 separation of the Solasteries of De Blainville from the ge- 

 nus Stellonia, the Solasteries having, like all the other ge- 

 nera of Asteriae, but two ranges of suckers, while the true 

 Stellonia? have no less than four. This important distinc- 

 tion is borne out by a corresponding difference of general 

 habit. 



For some time back I have collected and described such 

 star-fishes as occur on the coast of the Isle of Man, where 

 they are found in great variety and abundance. All the 

 species hitherto recorded as British, with the exception of 

 four or five, enrich the Manx fauna. Could I have placed 

 any dependence on the descriptions and synonyms of British 

 writers, I would have merely enumerated such as I had 

 observed ; but as the catalogues hitherto published of Bri- 

 tish star-fishes present us only with meagre and unsatis- 

 factory details as regards species, and extreme confusion 

 and inaccuracy as regards the synonyms, I have thought 

 it best carefully to revise the character of each species, 

 and to collate the descriptions and figures of all the authors 

 referred to, the works of whom I have been able to con- 

 sult. 



Processor Agassiz divides the Asteriadae into three fa- 

 milies, the Asteriee, the Ophiurae, and the Crinoideae. — To 

 commence with the Asteriae. 



All the British Asteriae may be arranged under eight 

 genera, examples of all of which I have found in the Irish 



