188 ANNALS NEW YORK ACADEMY OF SCIENCES 



In looking over this rather confused array of facts and opinions, it is 

 evident that much of the inexactness in the use of generic terms is due 

 to carelessness on the part of authors in consulting original descriptions 

 and often to their not consulting them at all. This is particularly the 

 case with forms referred to Zaphrentis. There is a prevailing idea about 

 the character of this coral, but it seems to have arisen from the opinions 

 expressed by various authors as to what they considered the characters 

 should be, and not from a study of the original description and figures. 

 For instance, Thomson and Nicholson have restricted the genus Za- 

 plwentis, stating that it can be recognized 



"by the complete, or comparatively complete, development of the septal system, 

 the great development of the tabulae, the existence of a fossula, which is formed 

 by the coalescence centrally of a certain number of the septa, and the fact 

 that the dissepiments are in no case sufficiently developed to form an exterior 

 zone of vesicular tissue." (14,428.) 



Carruthers in his discussion of Zaphrentis bases his generic description 

 upon that given by Thomson and Nicholson, adding that the description 

 "does not pretend to be founded on the specimens from which the original 

 diagnosis was prepared," but "it undoubtedly represents the genus as 

 understood at the present time." He retains the "conventional defini- 

 tion" and Salee, two years later, follows Carruthers. Thus authors have 

 been satisfied to take somebody else's interpretations, instead of going to 

 the sources. 



The last genus to be separated from Zaphrentis is Heliophrentis, de- 

 scribed in 1910 by A. W. Grabau (25, 98), with H. alternata Grabau 

 from the Upper Monroe as the genotype. This is a carinate species 

 closely related to and congeneric Avith Zaphrentis racinensis Whitfield of 

 the Niagara. These species may be congeneric with Zaphrentis cor- 

 nicula, and hence belong to the true Zaphrentis, but at present nothing 

 but the form and calicinal structure is known. 



I. Briefly reviewed, the facts are these : the genus Zaphrentis, first 

 described by Eafinesque and Clifford, was found by Edwards and Haime, 

 who probably had the type material, to contain only one recognizable- 

 species and that was Z. plirygia. This they considered the same as 

 Caryophyllia cornicula Lesueur, described from the same locality and 

 horizon, and called by them Zaphrentis cornicula. Since they gave the 

 first full and detailed description as well as figures, this species then be- 

 comes the virtual type of Zaphrentis. The distinguishing characteristics- 

 of the genus are as follows : 



