252 A. E. Verrill — Corals of the Genus Acropora. 



It agrees well with his description. I have never met with any 

 other example of the same species. It is easily recognizable on 

 account of its peculiar, more or less urceolate radial corallites, Avhich 

 have thin walls, often constricted below the aperture. 



It is very unlike the type of corymbosa described by Brook, 

 which is nearly allied to A. spicifera, A. cytherea, and A. surculosa. 

 Dana states that this species is caespitose, but our fragment is insuffi- 

 cient to determine the form of growth. It is a single nearly straight 

 branch, 50 mm long and 10 in diameter, with four divergent branchlets 

 arising from one side, as if it were a proliferous submarginal branch 

 from the upper side of a corymbose or ca j spitose clump. The 

 branches are tapered, obtuse. 



Axial corallites are rather large and prominent, 3.5 mm in diameter 

 and 2-3 mm exsert, with thick, porous, closely echinulate walls and 

 funnel-shaped calicles, about 1.5 mm in diameter. 



Radial corallites are thin-walled, and unequal in size and form. 

 The larger ones are rather large and prominent, S mm long and 2-2.5 

 in diameter, standing mostly at angles of 45° to 60°, and sometimes 

 in vertical rows. They are tubular, mostly somewhat swollen in the 

 middle and rather suddenly narrowed or constricted just below the 

 orifice, so as to give them an urceolate form; but many are scarcely, 

 if at all, swollen, and have the outer lip incurved, and often slightly 

 beaked, or with the edge lacerate. 



The aperture is round, oblique, and looks upward and inward. The 

 corallites are not at all appressed, and the inner lip is usually free 

 for some distance. The walls are thin, but firm, not costulate, but 

 thickly covered with rather strong, sharp, rough sphmles, sometimes 

 arranged in costal rows. 



Between the larger corallites are many that are small, short- 

 tubular, or verruciform, with the calicle terminal and the lips 

 lacerate. 



Septa distinct, but all narrow; the secondaries often rudimentary 

 or abortive. 



The coenenchvma is firm, irregularly pitted, thickly covered with 

 sharp spinules. 



Precise locality unknown, E. Indies or Indian Ocean (Dana). 



This species differs from all others known to me in the swollen 

 and urceolate form of the radial corallites, with their spinulose walls. 



. 1. neglecta Ver. approaches it, in this respect, more nearly than 

 any other species. 



