238 A. E. Yer rill— Corals of the Genus Acropora. ■ 



I will add the following details from one of my types : 



The ccenenchyma is veiy finely and evenly echinulated, and 

 almost without visible pores. 



The radial corallites are mostly short, verruciform, but some are 

 long, tubular, tapering from a thickened base ; there are also many 

 small immersed calicles. The radial calicles are all small, but thej^ 

 mostly have 12 septa, those of the second cycle being very narrow; 

 those of the first cycle meet below, as seen in sections. 



Wall of the axial calicles is thickened and rounded at the margin; 

 the sides are without costae. In sections the wall is thick and nearlj^ 

 solid, and the ccenenchyma is dense. 



Ousima. No. 1686. 



It is nearer A. procumhens (Br., p. 188, pi. xxviii) than to longi- 

 cyathus. It also resembles, in a general way, A. suhglabra (Br.), 

 and A. Rayneri (Br.). 



Acropora stellulata Ver., sp. nov. 



Plate XXXVI C. Figure 3. Plate XXXVI F. Figure 10. 



Coral arborescent, loosely and sparingly branched, with long slowly 

 and regularly tapered, terete branches, which often diverge at an 

 angle of 50° to 60°. The larger branches are 12 to 14°^'^ in diameter, 

 or more ; the undivided distal ones may be 70 to 100™°^ long, and 

 lO""" in diameter, VO"""" from the end. 



The axial corallites are of moderate size (2 to 2.5'^™), cylindrical, 

 a little exsert, with somewhat thickened porous, strongly costulate 

 walls, bearing small buds close to the end; the costute are regular, 

 thin, and high. 



The radial corallites are small, tubular, squarrose, short and stand- 

 ing nearly at right angles on the larger branches, but becoming- 

 longer and slightly ascending more distally. The larger ones on the 

 distal half of the terminal branches are longer than broad (about 

 ^mm ))road and 2™" high), slightly or not at all compressed, not 

 tapered, obliquely truncate, with the outer lip rounded, a little 

 thickened, and slightly incurved; the inner lip thin. Their walls are 

 porous, sometimes reticulate-porous, and strongly costulate, with thin, 

 high costulae. Between these are scattered many smaller, short, 

 tubular corallites, mostly squarrose and with reticulate walls. 



On the larger branches the corallites are of more uniform size and 

 length, very squarrose, short tubular or sub-verruciform, not so high 

 as broad (diameter about 1™™), with the calicle terminal and about 

 0.5 broad. Wholly immersed corallites seldom appear, except a few 

 on the under side of a single injured branch. 



