168 A. JE. Verrill — Bermudian and West Indian Reef Corals. 



round, 35 to 20 mm in diameter, regularly and gradually tapered, 

 often curved or even hooked. They grow isolated on a bottom of 

 shell-sand aud mud, in 12 to 15 feet of water, near Nassau, N. P., — 

 coll. R. P. Whitfield. 



This species, in its several varieties, is abundant on the Florida 

 Reefs and throughout the West Indies. It is also common as a 

 fossil in the raised reefs of various islands. It does not occur at the 

 Bermudas, nor on the Brazilian coast. 



It has been recorded from the East Indies, etc., by Brook and 

 others, but perhaps all such records are erroneous. I have seen no 

 authentic example of either variety from the Indo-Pacific region. 



It does not occur at Panama, nor elsewhere on the Pacific coast of 

 America. The genus is absent from that coast, except A. crassa (E. 

 and H.), recorded from the Galapagos Is. 



Gregory (Ann. and Mag. Nat. Hist., 1900, pp. 20-31) gives details 

 of the Indo-Pacific specimens, recorded b}^ Brook, after an examina- 

 tion of the types, and concludes that none of them belong to either 

 of the West Indian varieties, but to distinct species. The Singapore 

 specimen, referred by Brook to palmata (No. 93, 4, 7, 24), may be 

 the true alces of Dana. According to Gregory, it is distinct from 

 palmata in its calicles and coenenchyma, but grows in the same form. 



The Madrepora ethica D. and M. (op. cit., p. 82, 1860) seems to 

 be a dwarfed or young, slender form of var. prolifera. But the figures 

 referred to it (pi. x, figs. 7, 8) do not agree with the description at 

 all. They appear rather to represent a Millepora. 



This species, in all its diverse forms of growth, retains pretty 

 constantly the characteristic forms of its axial and radial or 

 lateral calicles, and the characteristic porous and g 



roughly echinulate texture of the coenenchyma. «&» 



The radial corallites and their calicles are a-S S$jM - 

 larger than in most species of the genns. The -VT -'„^ v rj^£ 

 corallites are rather openly nariform or tubo-nari- -);-J~ ^~V^ f 0£ : 

 form, costate, and porous. The septa are well 



\ -yc- 



i h 



J* 



developed, the directives wider. The axial coral- 3 ->V^ 



lites are stout, tubular, usually much exsert, not 



J Fig. 8. — Acropora 



swollen ; walls porous and strongly costate exter- muricata, var. pro- 



nally ; calicles large, tubular ; primary septa well t^^^IZr- 



developed, subequal ; secondaries narrower; the allitesare too small 

 septa form a distinct, ]2-rayed star. 



Errata. — Page 51, line 3 from bottom, for Flaggs read Flatts. — Page 128, 

 line 17, for xxxiii, fig. 4, read xxv, fig. 3. 



[For explanation of plates, see end of Article IV. J 



