184 EOCENE AND LOWER OLIGOCENE CORAL FAl'NAS. 



very thin and very porons, naked, no epitheca. Broad costae coiTespond to 

 the septa of the first and second cycles; a single broad costae usually 

 coiTesponds to the combined septa of the third and fourth cycles; they are 

 irregular in their development; all are minutely granulated. There are 

 four cycles of septa in the type species. They are very perforate near the 

 wall. The upper margins slightly exsert; the margins of the larger septa 

 subentire, with some faint dentations, or occasional crenations ; those of 

 the smaller septa spiniform dentate. The septal faces striate, the striae, rather 

 remote, with comparatively tall, round-pointed granulations distributed along 

 them. The trabecular construction seems to be the same as in Eupsanunia 

 and Balanophyllia. Columella very lax and spongy. This genus presents 

 such distinct characters that it can scarcely be compared with any other 

 Eupsammid genus. It would group in Duncan's alliance Balanoj^hyllioida, 

 and probably has most resemblance to Endopachys, but differs in such 

 important characters that a special resume is not necessary. 



RHECTOP8AMMIA CLAIBORNENSIS Sp. IIOV. 



PI. XXI, figs. 11 to 13. 



Corallum small, straight, firmly attached by a pedicel to some object; 

 in the specimens liefore me the attachment is iisually to a small gasti'opod 

 shell. Above the pedicel the corallum flares out rather suddenly. There 

 mfivl)e slight ma rg-inal wings. Cross section of calice elliptical. The wall 

 is thin and very perforate. There is no epitheca. The costa?, are poorly 

 developed; corresponding to the first and second cycles of septa, they are 

 moderately distinct. For the third and fourth cycles they can scarcely be 

 distinguished, or a low broad costa may correspond to the two cycles 

 combined in one half system. They are vesicular. 



The septa consist of four complete cycles in six systems. Those of 

 the fourth cycle meet in front of the third. The first and second (and pro- 

 longation from jimction of the fourth) meet the columella. They are very 

 thin, and tlieir sides are covered with small spines. Columella spongy. 

 The calicular fossa is deep. 



