182 EOCENE AND LOWER OLIGOCENE CORAL FAUNAS. 



Geologic occurrence. BgIIs Laildillg" iincl WoOcl.S Bluff bcfls. 



Type. — Academy of Natural Sciences of Philadelphia. 



Specimens. — United States National Museum; collection of T. II. Aldrich; 

 and Wagner Free Institute of Science. 



The following is M. de Gregorio's original description of Placosmilia 

 (Trocliosmilta) connivens de Gregorio (PI. XXI, figs. 8 to 9a) : 



"Tr. conoidea, simplex, elegans, calice elliptico, paulo excavato; septis 

 numerosis in 6 cyclos dispositis, laminaribus, tenuibis, valde angulosis 

 spinulosisque, apud columellam vix incrussatis; columella carente vel 

 cellulosa, ficta; costulis exterioi-ibus confertis, minutis, granulosis." 



Translation: "Tr. conoid, simple, elegant; calice elliptical, slightly 

 excavated; septa numerous, disposed in 6 cycles, thin, delicate, with very 

 sharp minute spines, thickening near the columella; columella absent or 

 cellular, false; external costje crowded together, minute, granular." 



The description suits Eiipsamniia elaborata except for the number of 

 cycles of septa, and the columella is never absent. E. elaborata has only 

 five cycles of septa, il. de Gregorio's figures for the side view of his 

 species, and the outlines of the calice, answer for E. elaborata, and only five 

 cycles of septa are represented. In the arrangement of the septa, however, 

 his drawings do not represent what is found in Conrad's species. The 

 septal diagrams given by M. de Gregorio for other species of corals that I 

 know well are not accurate, so it is not improbable that these likewise are 

 not correct representations of what is found in the specimens. I believe 

 that il. de Gregorio has redescribed E. elaborata. 



The following notes are made on the more minute structure of the 

 species. The structure of a cross section is practicall}" the same as in Bala- 

 nophyllia irrorata, except corresponding to each septum is a distinct, sharp, 

 single costa. The distal spongy zone of the two genera is the same. The 

 wall is made up of a network of false and true synapticulse, and the costse 

 sometimes fuse laterally. 



One instance Avas seen where apparently a new septum was being intro- 

 duced. Here the costa was double; the large septum corres})onding to 

 one side and the rudimentary septum corresponding to the other. This is a 

 reproduction of the condition previously described for Balanophyllia. 



The sides of the septa are minutely striate, with a considerable number 

 of granules along the courses of the stria-. The stria^ '"'ly he directly con- 



