54 Prof. P. Martin Duncan — On Cretaceous Madreporaria. 



Wiss. t. vii. p. 120, pi. 7, fig. 7, 8, and fig. 9-11 ; also M. Ed. and 

 Haime, Ann. des Sci. Nat. 3rd ser. t. x. pi. 7, fig. 7 and 8) ; but it is 

 as well to call attention to the fact that perfect specimens of Podoseris 

 have convex and more or less hemispherical upper surfaces, and that 

 their bases are perforated, whilst there are synapticulas between the 

 septa. The form is not a social one, and never springs from stolons 

 like Bhizangia, which has a wall, a flat upper surface with a shallow 

 calice, and is seated upon a stoloniferous base which may extend 

 beyond and give origin to others. 



The figures given by Mr. Tomes (7 and 8) show that there are no 

 stolons present. A stolon is a structure on which the bases of coral- 

 lites grow, and it is not a growth from the edge of the base of a 

 corallite. In the very numerous specimens of Podoseris from the 

 Eed Chalk which the Eev. Mr. Wiltshire placed at my disposal there 

 were no traces of stolons. No union by stoloniferous growth existed 

 in the specimens which were exhibited by Mr. Tomes at the Geol. 

 Soc, and although he states that " three corallites are united by the 

 stolon" (p. 552), it does not appear in the illustration (Fig. 7). I 

 especially drew attention to the want of stolons and such union in 

 the remarks I made on Mr. Tomes's paper at the Geological Society, 

 and my remark was published in the Abstract of Proceedings. 

 Nevertheless, Mr. Tomes persists in stating what he cannot sub- 

 stantiate. 



I draw attention to Mr. Tomes's Fig. 10, which professes to repre- 

 sent synapticulaa. On Plate XIV. is printed "E. P. Tomes, del.," so 

 that this is not a mistake of the artist. The figure proves that its 

 author has views regarding the nature of synapticulse which are not 

 those of any other zoopbytologist. Synapticulae pass from one 

 septum to another. In Fig. 9, synapticulas are called dissepiments. 

 Figure 11 of the Plate is acknowledged to be wrong, and should not 

 have been printed, for it leads to a mistaken view of the structures it 

 purports to represent. Syzygophjllum, Eeuss, is not in the least 

 like a Podoseris, and is synonymous with Antillia, nobis, a sub- 

 genus of Circophyllia ; it has no stolons. Podoseris is a well-defined 

 natural genus and is one of the Fungidaa, and Bhizangia is one of the 

 Aporosa. 



Turbinoseris, nobis ("Eevision of the Genera," p. 148). This genus 

 is stated by Mr. Tomes to be synonymous with Leptophyllia, Eeuss. 

 They are distinct for morphological reasons. Pratz in his article 

 (Palasontographica, 1882, p. 90) has shown that the septa of Lepto- 

 phyllia are numerous, thin, often uniting and composed of vertical 

 trabeculee with vertical rows of perforations between them. It may 

 be remarked that this lattice-work condition is not the result of 

 fossilization or weathering, but that it is normal, and necessitates the 

 species being placed with Cyclolites and other forms in a special 

 family of the Fungidge. 



Turbinoseris has many species, and I have described them from 

 the West Indies and ft*oni Sind, besides from the British Cretaceous. 

 In all, the septa are solid, and that is sufficient to separate the two 

 genera. Turbinoseris remains a member of the Lophoserine group 



