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Show 1887.] FROM THE ANDAMAN ISLANDS. 141 by Dr. Anderson; and Dr. Herbert Carpenter, F.R.S., has promised to discuss its relations to A. pal mat a in the report on the Crinoids of Mergui which he has in preparation. ASTEROIDEA. ACANTHASTER ECHINITES. M. de Loriol has lately pointed outl that the species oi Acanthaster found at the island of Mauritius is not, as has been supposed, A. echinites ; a comparison of his description and Mauritian specimens with the figures of Ellis and Solander and examples from the Andamans will be sufficient to show the student the distinctness of the species. As the difference has only lately been pointed out, and the confusion cleared up, it is as yet too early to say whether A. echinites belongs to the eastern, and A. mauritiensis to the western side of the Indian Ocean, or whether their areas of distribution overlap. FROMIA INDICA. I have elsewhere2 given my reasons for regarding this species, described bv Prof. Perrier as six-rayed, as being normally quinque-radiate ; a five-rayed specimen in the present collection has R equal to 33, and ?- = 9. With it are two specimens which possibly belong to a different species of the same genus ; they are smaller and are still quite spiny. CULCITA SCHMIDELIANA. There is a very remarkable specimen which I fancy I am hardly wrong in describing in detail ; another is of the more ordinary character. Almost round ; the apices of the ambulacra just touch the equator, so that R is almost exactly equal to r; the ambulacra narrow rapidly after reaching the actinal periphery. The ordinary arrangement of the adambulacral spines is as follows :-In tbe innermost row four subequal spines, beside which there may be a fifth smaller ; outside of and touching these there may be one large or two smaller spines, and either one or both occupy as much of the side of the groove as do the four spines internal to them ; outside of the second there is a third row which is more irregular, especially in the region of the actinostome. All the spines are stout, and more or less rounded at tbe tip. The interambulacral area, which is thickly covered with flat-headed grains, is almost perfectly triangular in shape; the number of grains in a patch varies; the patches are more closely packed in the middle than at the sides of the interambulacral triangle, and scattered among them are the ordinary granules. Peripherally the patches of grains cease somewhat rapidly ; a band, bare of patches, but granular and with sparsely scattered tubercles, 1 Mem. Soc. Phys. Geneve, xxix. no. 4, p. 6. 2 Proc. Zool. Soc. 1882, p. 123. |