BULI>F.TIX 5!), UXITEO STATKS XATIONAL Mrsi'.rM. 187 



Calicos from 1 to 2 iiiiii. in diaiin'tor, witli hctwccn 1.5 uiul l.'i, >lii,'-litly more 

 tlmn 1.5, as average, excavated, but shallow low down on the coralluni, inoderatelj' 

 diM'|) hiii'li u]) on the bnmclu's; scpaniti'd hy distinct, continuous walls, which on the 

 upper portion of the branch arc tall, sharp-cdyed, and nicmbraniforni, with leiuark- 

 ably few perforations. Mural denticles to a calice about twice as numerous as the 

 septa. 



The septa are of only moderate thickness or are even thin; usually sliyhtly nar- 

 rower than the interseptal loculi. Between a palus and the wall there is usually one 

 septal trabecula, except near the lower edjre of the livin<j portion where two is of 

 frequent occui-rence. Granules on the septal margins correspond to the trabecuhe. 

 The single, or the outer granule if two are pi'esent, is deUiched from the wall, being 

 separated from it by a sinus. The granules arc tall, but usually do not reach the 

 level of the edge of the wall. A ring of synapticula, usually detached from the 

 wall, extends to their bases and binds them together. 



The pali are well developed, but not so tall as the septal granules, thus giving an 

 excavated appearance to the central part of the calices. The formula is normally 

 complete. A complete ring of palar synapticula is usually present. 



The columella is a rather small, compressed tubercle, situated in a rather shallow- 

 pit, bounded by the inner edges of the pali. It is joined to the pali bj- radial 

 connections. There may be considerable stereoplasmic deposit around the axial 

 structures, rendering them rather compact. 



The interseptal loculi are so cut up by the two synapticuiar rings, the thickened 

 axial structures, and the rough sides of the septa that they are narrow, in spite of 

 the septa being thin on their upper edges. 



The skeletal surfaces are roughh' and rather coarsely granulate. 



Locality. — Hawaiian Islands, U. S. Expl. Exped. ; no more definite locality. 



Specimen here de><erihed. — Cat. No. 707, CS.N.M. 



Remarls. — Dr. W. T. Brigham has sent me a specimen from Kaneohe, Oahu, 

 that I am placing with this forma. It is 13 cm. long; greater diameter near lower 

 end, 3.t>5 cm. ; lesser, 2.7 cm. ; bifurcation, 4.1:5 cm. below the sunnnit. The branches 

 show constrictions and swellings, and taper to an obtuse apex. 



The calices average about l.S nmi. in diameter; and there are usually two septal 

 graTudations ])etween a palus and the wall. The skeletal structures are somewhat 

 thinner than in the Dana specimen. 



This forma, or "variety," to use Dana's expression, is not closely related to 

 P. mordd.r, as Dana thought, but possesses the same structural characters as 

 P. compressa. 



Forma ehmgnta may be considered a growth foiin of eithei- forma amjungens 

 or foi'ma uhacns. 



PORITES COMPRESSA forma PROFUNDORUM, new. 



I'lateLXXVI, li^s. 2, -In, S. 



Corallum composed of a tall, subterete, rather crooked main branch, which is 

 girdled hy irregular swellings and constrictions, and on whose sides are distant, 

 curved lateral l)ranches. The ends of the branches are rounded, obtuse and 

 compressed. Tlu> type material consists of sev(>ral broken Inanciies, some of which 



