1881.] PROF. F. J. BELL ON THE GENUS ASTERIAS. 511 



On comparing this with one of Mr. Norman's specimens, in which 

 R=16, r=3, we are at once struck by the greater development of 

 spines on the abactinal surface of the latter, where it is possible to 

 make out five very distinct rows of spines, while in the former only 

 three are to be accurately distinguished. In consequence of this 

 difference the specimens do not, as may be imagined, present any 

 very close resemblance. When we refer to the original description of 

 Sars we find some explanation ; for he says, " Auf dem Riicken 

 derselben 3-5 Reihen, von denen 3 deutlich, die 2 anderen weniger 

 deutlich oder hiiufig unvollstiindig sind." Though no two specimens 

 in the set of seven which were taken off Shetland differ from one 

 auother so markedly as do the two just referred to, yet they differ 

 sufficiently to show that the specimens of the species which are 

 found in the British Seas, just as much as those found off the 

 Scandinavian coasts, do vary, in this particular, within very wide 

 limits. The spines on Mr. Norman's specimens seem to be sharper 

 and rather longer than those on the specimen named by Dr. Liitken. 

 The proportions, and the resulting general appearance, are very 

 much the same ; and I can see no reason why the specimens should 

 not all be regarded as members of the same species. 



The above discussion contains an answer to the third question ; for 

 in demonstrating the characters of A. muelleri it proves the dis- 

 tinctness of that species from A. glacialis. 



The consideration of exceptional forms from the British seas may 

 well be postponed for further information and a larger series of 

 specimens. 



In here describing some forms under new names I am taking the 

 course which, after careful consideration, seems to me to be at pre- 

 sent that which is best adapted for the advancement of science. 

 The exact limits of the species of this genus can only be defined by 

 enermous collections. 



Descriptions of new or rare Species. 

 AsTERiAS PHiLippii, sp. uov. (Plate XLVII. figs. 1, la.) 

 It is necessary to make this new species for two specimens 



preserved in alcohol, and forming portion of the old Haslar collection ; 



they were collected by J. O. Goodridge, Esq., Surgeon R.N., and 



are stated to have come from "South America." 



General formula »^2maa'. 



Rays six, rather stout ; disk moderate ; adambulacral spines in two 

 rows, madreporic plate single, anechinoplacid, lateral and actiual 

 spines autacanthid — general formula V2maa'. The adambulacral 

 spines present a remarkable appearance, owing to their small size, 

 their delicacy, and their close packing ; in addition to this the 

 integument around them is raised up into processes almost as long 

 as the spines, and thus increases the appearance of crowding. A 

 well-marked groove separates these from the outer spines, of which 

 there are two rows on the actinal surface, while a third occupies the side 

 of the ray. All these spines, the best-developed of which may be as 



