258 EEPORT— 1882. 



specimens from the Jurassic formations in the cabinet of Mr. Longe. The 

 cells are very similar in character, both in their worn and in their perfect 

 state. 



Two other species — D. WrigUi (D. foUacea of Mor. Catalogue), and 

 D. Mettensis — are both Inferior Oolite types ; the first ranging from the 

 Inferior to the Great Oolite in this country. The B. Wrighti also may be 



the Bidlastopora and Mesenteripora meandrina of D'Orb. Mr. Lono-e 



who has made careful observations on the species — has selected for illus- 

 tration the most typical features of cell arrangement and character of the 

 two types ; and Dr. Woodward, in the beautiful plate which illustrates 

 Mr. Longe's paper on the ' Escharoid Forms of Oolitic Polyzoa,' ' has 

 doneample justice to the selection. A comparison of the two types of 

 cell in figs. 2 and 3 of that plate will give special details of structure 

 sufficient to justify Haime in their separation as species. It must not be 

 supposed, however, that the character and arrangement of the cells are 

 always so clearly defined as in the plate. The cells vaiy very much, and 

 it may be possible to find similarly shaped cells to these in other species 

 of the Oolitic Diastopora. 



Haime gives us another type of Diastopora cell as found in a species 

 in the Inferior Oolite of this country, and also in the Great Oolite of Ran- 

 ville and Caen. In the plate already referred to (fig. 4) Mr. Longe has- 

 selected for typical illustration a specimen from Caen. Haime calls it D. 

 lamellosa, Mich., and gives as its synonyms Elea, Multelea and Latere- 

 mtdtelea Banvilliana, D'Orb. and Eschara Banvilliana - of Michelin. 

 Relying upon the evidence of Mr. Longe, I cannot help but select his 

 opinion on this type. Speaking of the illustration, pi. 11, fig. 4, ' Geo. 

 Mag.' Jan. 1881, he says, ' I have little doubt but that this form is the 

 JEschara Ranvilliana of Michelin. In his figure the areolation is slightly 

 more angular than in the part shown in (my) figure. Jules Haime has 

 classed a somewhat similar form as B. lamellosa. D'Orbigny's EscJiara 

 or Elea triangularis is evidently a very similar form.' ^ The type of cell 

 I am not familiar with as a British species. 



In the Biastopora Waltoni, Haime, and in the B. Bavidsoni, Haime, one 

 from the Inferior Oolite near Cheltenham and the other from the Great 

 Oolite Hampton Cliffs, we have types of cells far from being unique. The 

 same may be said of the cells of B. Eudesana, Haime, also a Great Oolite 

 type. _ The same peculiarity of cell structure and arrangement may be 

 found in some of the adherent or encrusting Biastopora, as in the more 

 richly developed foHaceous species, but whether the foliaceous species as 

 a whole are developed from the encrusting forms I am unable to say. In 

 all probability they may have been so, and this would justify the Rev. 

 T. Hincks in breaking up the artificial divisions and classifying the 

 foliaceous and the encrusting species under one generic term. 



In the B. cervicornis,^ Michelin, of which species the Bidlastopora and 

 Elea cervicornis of D'Orb. are synonyms, we have very insufficient data to 

 deal with. It is said to occur both in the Great Oolite of Ranville, and in 

 the Bradford Clay of Pound Hill. I am not acquainted with the species 

 as a British type. 



' Geological Magazine, January 1881. 



* A beautiful illustration of this type is o-iven in Nicholson's Palceontclogy, vol. i, 

 420, fig. 270. ■'^ r. vy, r 



' Geo. Mag., January 1881, pp. 33, 34 ; descriptive text of fig. 4. 



* For illustration, see Nicholson's Palceontology, vol. i. p. 431, fig. 272. 



