228 Reviews — Z)r. M. C. Slopes — Mesozoic Plants. 



II. — Catalogue of the Mesozoic Plants in the British Museum. 

 Part V: The Cretaceous Flora. Part 1 : Bibliography, Alg^, 

 AND Fungi. By M. C. Stopes, D.Sc., etc. pp. xxiv, 286, with 

 2 plates and 25 text-figures. London : Dulau & Co., 1913. 12s. 



IT is now ten years since the last part of the Catalogue of Mesozoic 

 Plants was issued. The first four parts, by Professor Seward, 

 dealt with the Jurassic and Wealden Floras, and the work is now 

 being continued into the Cretaceous by Dr. Stopes. The present 

 volume consists mainly of an exhaustive bibliographj^ of the flora 

 of the period, which unfortunately could only be brought up to the 

 end of 1910. The list of species, which is not intended to be critical, 

 contains references as far as possible to every Cretaceous plant, with 

 the name and horizon originally given. The Wealden of Europe is 

 omitted, since it was dealt with by Professor Seward, but the lower 

 Cretaceous of North America, with its rich flora, is included. Though 

 many cross-references are given in cases where species have been 

 removed from one genus to another, no attempt has been made to 

 make the list complete in this respect, as Dr. Stopes only includes 

 "any renaming that was enlightening, or accompanied by any 

 original work on the specimen". Nevertheless, the list will form 

 a useful work of reference for future workers in this department 

 of fossil botany. 



The descriptive part of the catalogue deals only with the Algae 

 and Fungi, and owing to the scarcity of well-authenticated fossil 

 examples of these groups, there is not much to be said about them. 

 In the case of the algae the calcareous forms are the most 

 interesting, since their structure can often be studied under the 

 microscope, while recently their importance as rock-builders has 

 been much discussed. Several genera of the Siphoneae are repre- 

 sented in the Cretaceous, besides the red alga Lithothamnion. The 

 remaining "algae", apart from diatoms, are impressions only, and 

 though some are probably of an algal nature the great majority 

 are extremely doubtful. Dr. Stopes gives a list of seventy-eight 

 "species" which may be dismissed as mere tracks or indeterminable 

 specimens. 



The Fungi are even more poorly I'epresented. Only four of those 

 enumerated occur in a petrified state, and one of these, Trametites 

 pini (Conw.), is merely a mycelium, while Petrosphteria japonica, 

 Stopes & Fujii, is little better, and shows no reproductive organs 

 by which its family might be determined. In Trichosporites Conwentzi, 

 Felix, spores are associated with the hyphae, but the illustration shows 

 no evidence of attachment. The only well-preserved species is that 

 called Pleosporites Shiraimis, Suzuki, but even here the apparent asci 

 contain no ascospores, so that the generic affinities are doubtful. 

 Dr. Stopes suggests that different "biological species" of this fungus 

 may have been adapted to the different species of Cryptomeriopsis in 

 which it occurs, but are such "biological species" found among 

 Ascomj'cetes at all? The other "phenomena described as fungi" 

 are markings on leaves, often of a verj' doubtful nature. Dr. Stopes 

 uses Gothic type for the names of "fossil plants for which there is no 



