254 REPOET— 1882. 



I am unable to say. In another direction a similar colony will be de- 

 veloped, the distal cells of which will ultimately meet and coalesce, both 

 colonies striking out in fresh directions till met by another check, the 

 growth not always being in an upward direction. The dendroid 

 character of species is perfectly accidental. 



With regard to the proper location of the type authorities differ. Pro- 

 fessor Busk places it in the family Idmonidce. In referring to Heretopora 

 (' Crag Polyzoa,' p. 121) he says, ' Milne-Edwai-ds, in his second edition of 

 Lamarck, 1836, placed amongst the heterogeneous Polypiers foramines, 

 Pustulopora, Ohrysaora, Theonoa, and Terebellaria.' Jules Haime places 

 the genus immediately after Idmonea and before Berenicea, and it is near 

 to, or, if need be, as a sub-genus of, Diastopora that I would be inclined 

 to leave it. In accordance with this I think it will be best to redescribe 

 the species. 



Terebellaeia ramosissima, Lamx. 

 1816. Millepora, William Smith. — (Clay over Upper Oolite.) 

 Terebellaria. — (Of authors generally.) 



Zoarium, a thin riband-like layer of cells encrusting foreign bodies, or 

 coiling itself upon its own previously formed zoaria, ultimately assuming 

 a spiral, ramose, dendroid or massive form. Zooecia slightly elongated, 

 sometimes disposed in spiral lines, rather more produced at the distal 

 than at the proximal part of the cell ; peristome thick, orifice circular, 

 occasionally semi-circular, front of cell finely punctured. Ocecia, an 

 enlarged globose cell, having beneath the orifice a semi-civcular cluster 

 of punctures definitely arranged. 



Localities. — My own cabinet, Cornbrash, Stanton, Wilts ; Forest Marble 

 Box; Bradford Clay, Bradford, Wilts ; Mr. Walford's cabinet, rich from 

 several localities ; School of Mines. 



Genus Diastopora, Lamx. 

 Sy. with Berenicea (pars), Lamx. 



I am willing to accept this genus, in its wider sense, as defined by 

 Hincks ; yet I hardly think that it will be possible to include the whole 

 of the foliaceous forms of the Jurassic period in one group. In this 

 report I shall adhere to the arrangement of Busk, as I have done in my 

 two papers on the Diastoporidas, keeping the foliaceous types for distinct 

 study. At the same time I am willing to admit that in getting rid of one 

 difficulty in our grouping we open the door to admit others. Haime 

 admits both the encrusting and foliaceous types ; accepting the genus 

 Berenicea for the encrusting, and Diastopora for simple-foliaceous and 

 retiform species. Professor Braun, in his Jurassic studies, separates the 

 species Diastopora foliacea from the group and establishes another, which 

 he calls Elea, claiming for his type certain peculiarities which have been 

 entirely overlooked by authors. It is very certain that the more closely 

 we examine Jurassic Polyzoa and compare them with modern species of 

 the genus Diastopora, the more divergent the types appear; and although 

 we would rather accept a simple than an elaborate classification, still 

 there are limits beyond which it is not wise to go. 



The genus Berenicea was established by Lamouroux, and included in 

 it, beside the fossil species, B. diluviana from the environs of Caen — two 



