SEA LILIES, STARFISHES, ETC. CLARK. 57 



Family ASTERINID^. 

 Genus Asterina, Nardo. 



ASTERINA ATYPHOIDA,! Sp. nOV. 



(Plate xvii., fig. 1-2.) 



Remarkably similar to A. modesta, Verrill, from Panama. 

 On the upper surface the only difference is in the coarser 

 granulation of the plates in the Australian specimens. Actin- 

 aUy the difference is somewhat more marked ; the adambu- 

 lacral plates almost never have more than one subambulacral 

 spine, while in A. modesta two such spines are often, if not 

 usually, present ; the actinal intermediate plates near the 

 margin have only a single spine while in A. modesta there are 

 two and occasionally three. The largest specimen of A. 

 atyphoida is 19 mm. across; R = 10 mm., and r=8.5 mm. 

 Colour (dry), Hght brown or whitish. Four specimens. 



The resemblance between these South Australian Asterinas 

 and specimens of A. modesta from Panama is very extra- 

 ordinary, whether one regards it as indication of genetic 

 relationship or as a case of parallehsm. In either case, the 

 degree of difference is very slight in view of the fact that 

 several other species of Asterina occur in the vast intervening 

 distance between the homes of the two species. It is obvious- 

 Ij^ impossible, without far more data and specimens than are 

 now available, to determine what the relationship between 

 them really is. 



Locs. — Fifteen miles north-west of Cape Jervis, South 

 AustraUa, 17 fathoms. This specimen has been selected as 

 the ho lo type. 



Off Cape Marsden, Kangaroo Island, South AustraHa, 17 

 fathoms. 



Asterina leptalacantha,^ sp. nov. 

 (Plate xviii., fig. 3-4.) 



R = 18mm. ; r=8 mm. ; R=2.25 r. Br=9 mm. ; R= 

 2 br. Br at middle of ray =7 mm. ; at tip, 3 mm. Disk and 

 rays moderately arched, but general appearance flattened ; 

 margin formed by the conspicuous infero marginals. Abacti- 

 nal plates as usual in Asterina, more or less markedly 



1. (iTi;0o9=the Latin modestus-\-eico'i=iovrQ.; in reference to the 

 resemblance to A. modesta, Verrill. 



2. X67rT«\fc'os=fine, slender-f (4^01/^0= thorn, spine; in reference to 

 i;he verj' fine spines on the inferomarginal plates. 



