122 MR FORBES ON THE ASTERIAD,<E OF 



disk, lanceolate, covered as well as disk with clavate spines, encir- 

 cled towards their bases with a corona of from ten to fourteen spi- 

 nules. Among these spines are interspersed small, conical, flattened, 

 furrowed spinules. The spines in the centre of the rays form an 

 irregular ridge. Avenues bordered by three sets of spines : first, 

 ordinary .spines arranged in pairs ; second, thick spines arranged in 

 threes, surrounded and separated by bundles of spinules; third, a 

 double row of long, simple, smooth spines. Madriporiform tubercles, 

 striate, lateral. 



The commonest of all British Asteriadse, but involved 

 in great confusion as regards synonyms. There can be no 

 doubt, however, as to its being the true Asterias rubens 

 of the older authors, among whom Otho Fabricius de- 

 scribes it with great accuracy. The Asterias rubens of 

 Fleming is strangely enough compounded of this and So- 

 laster endeca ! That of Johnston is the Luidia fragilis- 

 sima. Blainville is correct in his references. The arms of 

 this species, especially of a common variety, in which the 

 primary spines are fewer, and somewhat larger than ordi- 

 nary, are apt to come off on handling roughly, but the 

 animal has no power of casting them off voluntarily, though 

 the next species probably possesses that faculty. Stellonia 

 rubens is the "cross-fish" and "five fingers" so much 

 dreaded by oyster fishermen as a depredator of oyster 

 beds. Stellonia violacea, Stellonia hispida, and perhaps 

 Stellonia seposita, occur on the coasts of Scotland, and have 

 been confounded with this species, but are easily distin- 

 guished by their proportions, (which are constant in all 

 ages of animals of this genus), and by the structure of 

 their spines. In the very young specimens of Stellonia 

 rubens there are no spinulse. The colour is also generally 

 purplish ; in the full-grown animal it is yellow, or orange- 

 red. Large specimens are more than a foot across. 



33, pi. 30, fig. 50, pi. 34 and 35, fig. 58, pi. 36, fig. 67, pi. 40, fig. 70. A. gla- 

 cialis, Fleming, p. 487 ; Penn. 4, p. 60, No. 54 ; Junior ; A. clathrala, Penn. 

 iv. p. 61, No. 55. 



