312 



DR. P. H. CARPENTER ON THE 



siderable size, but on the inner arms it is a good deal smaller 

 (PI. XXVII. figs. 1, 2). 



The chief point of difference between the Mergui and the Phi- 

 lippine specimens is in the size of the third pinnule, that on the 

 sixth brachial. In the outer arms of the Mergui individual 

 (PL XXVII. fig. 1) its length relatively to that of its predecessor 

 on the fourth brachial is but little smaller than in the type-speci- 

 mens from Zebu ; but on the inner arms (PL XXVII. fig. 2) the 

 difference between the second and third pinnules is more marked. 

 Those of the type specimens are sometimes nearly equal, though 

 not always so ; but in the Mergui form the difference is often 

 considerable (PL XXVII. figs. 1, 2) ; it is not so great, however, 

 as in Antedon protectee, in which the third pinnule is much reduced 

 in size, not only on the inner, but also on the outer arms. 



Actinometra notata, sp. n. (Plate XXVI. figs. 6-12.) 



d. p. p'. (p"). br.be 

 specific Formula. A. K. ^ ^jp 



Centro-dorsal a thick disk, bearing 30 or 35 marginal cirri. 

 These have about 25 joints, the later ones short and wide, with 

 but little trace of spines. 



First radials more or less concealed ; the two outer ones united 

 by syzygy. Arms 31 to 50 or more in number. The distichal 

 and palmar series each of two joints united by syzygy, with one 

 or two further divisions of the same character ; the first two 

 brachials also united by syzygy. The next syzygy is sometimes 

 in the third or fourth, but usually not till the tenth or fifteenth 

 brachial, and others follow at intervals of 2-4 joints. The lowest 

 brachials are nearly oblong, and their successors triangular and 

 wider than long, soon becoming more quadrate, and finally nearly 

 oblong again. 



The first pinnule is on the second brachial, and is very long 

 and flagellate with a large terminal comb, reaching nearly 40 

 millim. on the outside of the ray. The following pinnules dimi- 

 nish rather rapidly in length, and lose their comb after about the 

 eighth brachial, but never become specially short. The two basal 

 joints of the first three or four pinnules on each side are more or 

 less carinate. 



Mouth obscurely radial ; the disk may have calcareous granules 

 in the anal interraditiH, or be entirely naked. AH the arms are 



grooved. 



