76 



BERENICEA. 



II. Zooecia pyriform. 



Peristomes well raised ... ... ... ... spatiosa, "Waif. 



Peristomes low ; zooecia long ... desoudini (Haime) 



Zooecia short ... ... morinica (Sauv.). 



BERENICE A, Lamouroux, 1821. 



Diagnosis. Tubuliporidae in which the zoarium is a thin, flat, 

 encrusting sheet. The zooecia are tubular. The peristome is 

 either flush with the surface or somewhat raised. 



Type species. B. prominens, Lamx. [The B. olelia (Johnst.).] 



Affinities. Berenicea was founded by Lamouroux for a recent 

 Mediterranean species, generally known among zoologists by the 

 name given to it by Johnston twenty-six years later. The genus, 

 as here accepted, includes the flat, encrusting Tubuliporidae, while 

 Diastopora includes the erect, foliaceous forms. It has often been 

 proposed to merge the two, but the distinction is so convenient 

 that it is advisable, if possible, to retain it. The evidence that 

 one species is sometimes erect and sometimes encrusting, is very 

 insufficient. Eeuss 1 has made a species, D. corrugata, which, he 

 says, is sometimes erect and sometimes adnate. His figures, how- 

 ever, show marked differences between the two. In some recent 

 species growing upon the stems of seaweeds, I have seen cases 

 where the two sides of a Berenicea have met, and, pressing against 

 one another, have formed a small, free, bilaminate expansion. 

 But an exceptional and abnormal growth such as this hardly 

 seems sufficient to destroy a distinction, so well marked in the vast 

 majority of cases. 



A distinction which it is more difficult to define is that between 

 this genus and Tubulipora. The separation can only be based on 

 the condition of the distal ends of the zocecia. In the typical 

 species of Berenicea the peristome is either flush with, or raised 

 but slightly above, the general surface of the zoarium. In Tubuli- 

 pora, a great length of the distal end of the zooacia is free and 

 reflexed. There are some species, however, of Berenicea, such as 

 e.g. Berenicea spatiosa (see PI. Ill, Fig. 1), in which the peristomes 



1 A. E. Reuss. Tert. Bry. Kischenew in Bessarabia : Sitz. k. Akad. Wiss. 

 Wien. Bd. Ix. Abth. 1, 1869, p. 510, pi. i. figs. 6, 7 ; pi. ii. figs. 1-5. 



