FOSSIL CORALS FROM WEST INDIES WELLS 83 



ones 2.5 by 4,5 mm. Within the calices the septal margins fall 

 evenly but steeply to the central f ossette, the bottom of which is about 

 1.2 mm below the calicular margins, or 1 mm below the intercorallite 

 areas. The surface between the corallites averages 1.5 mm in width 

 and is crossed by the confluent septocostae, whose upper margins are 

 heavily beaded, owing to their trabeculate-fenestrate structure. The 

 septa are imperforate, laminar, thickened peripherally, thinner to- 

 ward the center, not extending to the center of the corallite, and 

 laterally granulated with the upper margins dentate. In a circular 

 calice there are regularly 24 septa, 12 of which are longer than the 

 rest and reach to the edge of the fossette, which they bound ; in larger 

 calices up to 45 septa can be counted, ail regularly alternating in 

 length. There is no columella. The synapticulae are developed only 

 in the peripheral region of the corallites. Between corallites there 

 is some exotheca but there is no endotheca within them. 



Measurements. — The holotype is 55 mm high, 32 mm in maximum 

 diameter, and 16 mm in diameter near the base. 



Eolotyp-e.—V.S.'^M, no. 74484. 



Occurrence. — In the limestones near Catadupa, Jamaica (Trech- 

 mann collection). 



Remarks. — This species may be distinguished from Synastraea (?) 

 adhinsi by its imperforate septa, by the presence of a synapticular 

 corallite wall, and by the fissiparous mode of increase. 



Family LEPTOPHYLLIIDAE Vaughan 



Genus DIPLARAEA Milaschewitsch, 1876 



DIPLARAEA (?) BOLTONAE. new species 



Plate 2, Figures 1, 2 



Description. — Corallum subcylindrical, compressed near the base, 

 expanding upwardly, subdividing into several corallites, which re- 

 main closely united in a single series, separated by constrictions of 

 the corallite wall and joined inwardly by short, confluent septo- 

 costae. Between the base and top of the corallum the exterior is 

 marked by irregular expansions, and in the type specimen midway 

 between base and top is a small protuberant corallite that has been 

 produced fissiparously and has remained separate. The exterior is" 

 covered by a very thin, easily eroded epitheca, through which the 

 septo-costae are seen. The latter are rounded, subequal, and beaded 

 on their edges. Between them and extending to the wall are well- 

 developed exothecal dissepiments. The wall is perforate, indistinct^ 

 and composed of synapticulae and dissepiments. The calices are 

 shallow and very irregular in outline. There are three on the top 



