Reviews — Igneous Rocks. 559 



Though contiuuity is lacking between these two phauts, there 

 seems considerable ground for suspecting them of belonging to 

 the same plant from anatomical points of likeness. 

 Araucarioxi/lon tanhoensis, sp. nov. Secondarj' wood, showing 



remarkably" clear pittings in the transverse sections. 

 Cedroxylon Matsuimirii, sp. nov. Well-preserved secondary wood. 

 Cedroxylon Yendoii, sp. nov. Secondary wood, with traumatic resin 



canals. 

 Cunninghamiostrohis yubariensis, gen. et sp. nov. A cone, as its 



name implies, belonging to the family of the Cunninghamias, 



with its external appeai'ance partly preserved and the cone 



scales and axis fairly well petrified. The seeds have apparently 



been scattered. 

 Cryptomeriopsis antiqua, gen. et sp. nov. Stem with leaves attached, 



the foliage very like that of a Cryptomeria. 

 Saurtiropsis niponensis, gen. et sp. nov; The stem and attached 



roots of an Angiosperm, probably to be included in. the 



Saururaceae. 

 Jugloxylon Hamaommm, gen. et sp. nov. The s> jiidary wood of 



an Angiosperm. 

 Populocaulis yezoensis, gen. et sp. nov. The stems of an 



Angiosperm, with cortical tissue. 

 Fagoxylon hohkaidense, gen. et sp. nov. The secondary wood of an 



Angiosperm. 

 Sahiocaulis Sakurii, gen. et sp. nov. Minute stems and older twigs 



of an Angiosperm, with cortex, and well - preserved and 



characteristic anatomy. 

 Cretovarium japonicum^ gen. et sp. nov. The flower of an 



Angiosperm, of which there are several specimens. 



Of this list of plants, the commonest, i.e. those which have yielded 

 the greatest number of specimens in the course of the work, are 

 Yezonia, Sabiocauh's, and Cretovarium. It is noteworthy that these 

 are among the most unusual and the most interesting of the plants.' 



I^E'VIE'WS. 



I. — Igneous Rocks: Composition, Texture, and Classification; 

 Description and Occurrence. By Joseph P. Iddings. In two 

 volumes. Vol. I^: Composition, Texture, and Classification. 8vo ; 

 xi + 464 pages, 130 figures, and 1 coloured plate. Cloth. New 

 York, John Wiley and Sous ; London, Chapman & Hall, Limited; 

 1909. 15 (21s.) net. 



rPHIS is the first part of a new textbook of the petrology of Igneous 

 1. Ptocks, and is meant to serve as an introduction to an exposition 



of the ' quantitative ' classification. For this reason special prominence 



1 The authors acknowledge much assistance in the work from the Eoyal Society 

 Government Grant Committee, which made it possible for one of them (M. C. S.) to 

 attempt the work ; and from the various departments of the Imperial Government of 

 Japan in the course of collecting and preparing the material. 



2 Vol. II : Description and Occurrence (in preparation). 



