BULLETIN 59, UNITED STATES NATIONAL MUSEUM. 1 V)3 



Diiiifniin to illvistrutc tlie intcrn'hiliun ul' the funua' of /''/•/7-.v r,,iii/>r--<.'<ii : 

 dcliciitula 



anj^ustisppta 

 frajjili- 



i)rot'uniiicil\ X ronjuriuens ]iil()sa densiiiiuiata griiiiiiiiur:it;i 



)inpressa (typical) 



divaricaiis 



conipac-ta 



tutiiida 



abacus 



bulbosa 



eloiijrata 



\ 



])n)fundoriiiii. 



iirt>\ iraiiiosa. 



3. PORITES DUERDENI, new species. 

 I'lati- I, XXVIII. li-. :;: PJiite l.XXIX, li^'s. 1. 1„. 



Coralluiu ramose, liraiiclics iiiucli fused helow, irreijjular in shape, with luiincr- 

 ou.s constrictions and swellings, ends often clavalc and more or less fused one to 

 another. Height, 1.5 cm.: lenoth of l)ranclies, up to 7 or S cm.: diameter, 2 to S cm. 



Calices excavated, with a deep central fossa, polygonal, large, fi'oin 1 to 2.5 lum. 

 in diameter, usually about 1.8 mm.; separated by an elevated, proiniiu'nt. thin, con- 

 tinuous wall. Mui'ai denticles of variabl(> prominence, llattiMied jiaralli^l to llie wall, 

 the muuber to a calice luore numerous than the septa. 



Septa rather thick, with thicker outer ends, therefore wedge-shaped : composed 

 of traliecnhe directed obliipiely upward and inward, their ends prodncing between 

 the pali and the wall fi'om two to four rather blunt dentations. '|"he outer one 

 attached to or slightly detached fi-oui the wall. .\n incomjilete peripheral ling of 

 synajiticula. somewhat detached from the wall, is present. 



The paii are only the inner septal teeth, which are tlie up|ii'r ends of the inwardly 

 inclined septal trabecula': they are small, low. and narrow, liy the fusion together 

 of the inner ends of th(> lateral pairs of septa, only a single tooth may stand liefore 

 a pair, l)ut in some instances a tooth may be l)efore each septum of a ])air. I'sually 

 there is a tooth before, or on tlie inner end of each Jaleial pair, of the dorsal 

 directive, and of each ineml)er of llie triplet: sometimes, howexer. there is none on 

 the ventral directive. These ti>eth liecome miMged with the columellar tangle. 



The coluniellar taTigle is relatively large, alxnit (•.T.i nun. in diameter, occupying 



about one-half the caliculai' cavity, surrounded by a ring of synajiticula. Its ujiper 



surface is dejiressed below the level of the palitVu'in dentations and bears one or 



several small i)apilhe. No detinite cohunellar trabecula could lie discovered in the 



32.'»1— 07 Vi 



