126 Rev. A. M. Norman on the Genera and 



Though scarce, it appears to have been found, here and there, 

 round our coast. We have ourselves taken it off Shetland and 

 the Northumberland coast, and have received it from Mr. T. 

 Edward, from the Moray Firth. 



Genus XX. Asterias, Linnaeus. 



[^Asterias, Linnaeus, 1748. Stellonia, Nardo, 1834 (partly). Ur aster, 

 Agassiz, 1837. Asteracanthion, Miiller & Troschel, 1840.] 



Body with five elongated, subcompressed or moderately con- 

 vex and often angulated rays, furnished with spines placed 

 singly, and either scattered over the surface or arranged in 

 regular longitudinal lines. No marginal plates or spines. 

 Suckers quadriserial. Anus central. Pedicellarise of one or 

 two kinds : the one small, with interlocking blades always pre- 

 sent and grouped round the base of the spines; the second 

 form much larger than the first, pincer-formed, and, when pre- 

 sent, scattered over the surface. Madreporiform tubercle situated 

 midway between the centre and the margin of the disk. 



Miiller and Troschel, in their ' System der Asteriden,^ have 

 wholly suppressed the Linnsean genus Asterias, and have been 

 followed by most Continental authors who have of late years 

 written upon the Echinodermata. Such a proceeding, however, 

 is on all accounts most undesirable, and wholly at variance 

 with the established laws of nomenclature. What species, then, 

 is to be regarded as the type of the Linnsean genus ? Opinion 

 has been in some measure divided between the Asterias ruhens 

 and the A. aurantiaca. It is to the latter species and its allies 

 that the genus was restricted by Agassiz, who was followed by 

 Forbes, as well as by Miiller and Troschel in their first memoir 

 in the ' Bericht der Berliner Akademie ' for 1840. But for this 

 species Linck had established a genus, Astropecten, in 1733. 

 His work ^De Stellis marinis^ was an excellent monograph, 

 when we consider the period at which it was published ; and b.y 

 general consent, and with great justice, his genus is now recog- 

 nized. There are other reasons, also, which seem to point 

 to Asterias rubens as the most proper type of the Linnsean 

 genus ', and we have therefore followed Dr. Gray in so regarding 

 it. Moreover, if Asterias were rejected as the generic name for 

 this species, Miiller and TroscheFs Asteracanthion could not be 

 adopted, since both Stellonia of Nardo and Uraster of Agassiz 

 have precedence of that genus. 



Asterias glacialis, Linnaeus. 

 Uraster glacialis, Forbes, British Starfishes, p. 78. 

 Rays distinctly angulated, having three distinct and very con- 

 spicuous longitudinal rows of large spines extending the 



