July 11, 1919] 



SCIENCE 



47 



of Cycadophyta by Mr. Hamshaw Thomas^^ 

 (now Captain Thomas) founded on material 

 collected by him at Gristhorpe bay on the 

 Yorkshire coast. This genus possessed fertile 

 shoots bearing small ovules and interseminal 

 scales crowded on a pyriform axis and sur- 

 rounded at the base by a whorl of micro- 

 sporophylls each bearing 5-6 synangia. The 

 bisexual shoots were almost certainly borne 

 in the forks of a slender dichotomously 

 branched stem like that of W ielandiella, and 

 there are good grounds for regarding the sup- 

 posed fern leaves known as Tacniopteris vittata 

 as the foliage of this Bennettitalean plant. 

 Mr. Thomas's discovery-^ of a bed of mummi- 

 fied plant remains in the Lower Estuarine 

 series at Eoseberry Topping, Yorkshire, en- 

 abled him to investigate minutely the epider- 

 mal characters of the problematical genus 

 Thinnfeldia; he believes that the fragments 

 of leaves and twigs of which the deposit is 

 mainly composed were borne on trees, an in- 

 teresting suggestion at variance with previous 

 views on the nature of the genus. This au- 

 thor also describes a Yorkshire specimen of 

 Williamsonia^^ in the Paris Museum which is 

 probably the male flower of Williamsonia gigas. 

 Miss Holden's account of a new type of 

 coniferous stem, Metacedroxylon-* from the 

 Corallian of Sutherland, Scotland, adds an- 

 other to an already long list of Mesozoic types 

 exhibiting a mixture of Abietineous anatom- 

 ical characters. An examination by the same 

 author^^ of impressions of Wealden fronds 

 previously referred to the genus Oycadites 

 and believed to be closely allied to the recent 

 Cycas shows that they should be transferred 

 to Pseudocycas. A paper by Mr. Clement Reid 

 and Mr. Grove^^ on Characese from the Pur- 

 beck of Dorset gives a preliminary accoimt of 

 their researches into the fossil representatives 



21 Phil. Trails. B. Soc, Vol. 207, Series B, p. 113, 

 1915. 



22 The Naturalist, January 1, 1915, p. 7. 



23 Proc. Cambridge Phil. Soc, Vol. XVIII., Pt. 

 III., p. 105, 1915. 



21 New Phytologist, Vol. XIV., p. 205, 1915. 



2= IMd., Vol. XIII., p. 334, 1914. 



26 Proc. B. Soc, Series B, Vol. 89, p. 252, 1916. 



of this neglected family; they describe a new 

 genus, Clavator, characterized by club-like 

 nodes on the stem and by other characters. 

 Dr. Marie Stopes has instituted a new genus, 

 Planoxylon,-' for a Cretaceous New Zealand 

 ©oniferous stem combining Abietineous and 

 Araucarian features; she suggests that this 

 generalized type points to the existence in the 

 southern hemisphere of an extinct group of 

 conifers of imexpectedly Abietineous afiinities. 

 The same author-^ describes the structure of 

 the first specimens of roots of Bennettites so 

 far discovered. 



Several papers by Dr. Ellis-" deal with fossil 

 fungi and include descriptions based on char- 

 acters of doubtful value of some supposed new 

 species from Jurassic and Cretaceous rocks; 

 the author also discusses the role of micro- 

 organisms in the formation of ironstones. 



4. Tertiary and Pleistocene Plants. — Mr. 

 Dutt's careful account of Pityostrohus macro- 

 cephalus,^" believed to be allied to Pinus ex- 

 celsa, from the Lower Eocene of the London 

 Basin is an interesting morphological contri- 

 bution and reveals the occurrence of unusual 

 features in this well-preserved Abietineous 

 cone which have been overlooked by previous 

 authors. Papers by Mr. Clement Reid^^ and 

 by Professor Marr and Miss Gardner^^ extend 

 our knowledge of the Arctic Pleistocene flora 

 of England and of the conditions under which 

 the plants grew. 



In his " Notes on Calamopitys "'^ Dr. 

 Scott deals with the same fulness and critical 

 insight with the known species of this Lower 

 Carboniferous genus, a type showing certain 

 affinities to Lyginopteris and Eeterangium. 

 We have unfortunately no knowledge of its 

 reproductive organs. The paper contains 



27 Annals of Botany, Vol. XXX., p. Ill, 1916. 



28 nid., Vol. XXXI., p. 257, 1917. 



29 Proc B. Soc Edinburgh, Vol. XXXV., Pt. I., 

 p. 110, 1915; Knowledge, Vol. XXXIX., p. 73, 

 1916; Geol. Mag., Vol. IV., p. 102, 1917. 



30 Annals of Botany, Vol. XXX., p. 529, 1916. 



31 Quar. Jour. Geol. Soc, Vol. LXXI., p. 155, 

 1917. 



32 Geol. Mag., Vol. III., p. 339, 1916. 



33 Jour. Linn. Soc, Vol. XLIV., p. 205, 1918. 



