58 " El«iDEAVOUR " SCIENTIFIC RESULTS. 



imbricating and with a proximal notch or concavity for the 

 subtending papula ; there are no small supplementary plates ; 

 across the base of the ray one may count 10-12 series of plates 

 but only 8 or 6 distally above the superomarginals ; at base 

 of ray there are 5-7 series of papulae but only three (or two) 

 extend beyond the middle of ray. Except for a few minute 

 spinelets around the anus and around the madreporite, all 

 the abactinal plates, but 10 or so in each interradial angle, 

 are perfectly bare and smooth ; the interradial plates referred 

 to each carry 6-10 exceedingly slender spines, .75 mm. long. 

 Superomarginal plates small and perfectly bare. Infero- 

 marginals about 24 on each side of ray, very conspicuous, 

 each one bearing a tuft of 12-15 (or more) exceedingly slender 

 spines 1-1.5 mm. long. Ac tino lateral plates in two complete 

 series, while a third runs as far as the twentieth (from inter- 

 radius) inferomarginal ; there are 5 or 6 plates in a fourth 

 series, and a few additional plates in the interbrachial arc ; 

 except the three most adoral plates of the first series, which 

 are perfectly bare, each of these plates carries a single, sharp, 

 relatively stout spine nearly a milhmeter long ; in each 

 interradial area except one, back of the oral plates, is a small 

 bit of naked, uncalcified skin. Adambulacrals about 26, 

 all but the two most adoral, corresponding to an infero- 

 marginal with the intervening actinolaterals ; armature 

 consists of a furrow series of 5 (4-6) spines, the middle one 

 longest, adoral and aboral ones shortest, and a single promi- 

 nent subambulacral spine on the surface of the plate. Oral 

 plates rather large, with only 5 marginal spines, the terminal 

 much the largest, and a single big spine on the surface. 

 Madreporite small, triangular, nearer centre of disk than 

 margin. Colour (dry), pale yellow-brown. 



This very interesting Asterina, while not collected by the 

 " Endeavour," is included in the collection sent me, and 

 certainly deserves description. It belongs in the section of the 

 genus to which Verrill has recently given the name Patiriella, 

 the type of which is A . regularis from New Zealand. But there 

 is little superficial resemblance between A . leptalacantha and 

 A. regularis and if Asterina is to be broken up, one would 

 hardly expect them to fall into the same section. The new 

 AustraHan species cannot be mistaken for any hitherto 

 described, the relatively long arms, the bare abactinal plates, 

 the remarkable inferomarginals and the spinulation of the 

 actinal surface forming a very distinctive group of characters. 



Loc. — Masthead Island, Queensland, collected by Mr. A. R. 

 McCulloch, December, 1913. 



