376 Reviews—French Tertiary Polyzou. 
II.—Conrrisutions To A Strupy oF 'prriary Potyzoa. 
1. Conrripurions A L’ETUDE DES Bryozoarrns FossItEs, No. xiv, 
Bryozoaires DU Stampiren. By F. Canv. Bull. Soc. Géol. France, 
ser. Iv, vol. xiv, pp. 147-52, pl. iv, 1914. 
2. Lxs BryozoaIRES FOSSILES DES TERRAINS DU Sup-OvEST DE LA 
France, No. vii, Rupéiren pe Gaas. By F. Canv. Bull. Soc. 
Géol. France, ser. Iv, vol. xiv, pp. 465-74, pls. xiv—xv, 1914. 
N these two papers M. Canu continues his investigation of the 
French Tertiary Polyzoa. Im one he discusses the age of the 
Argiles de Gaas, and concludes that they are Rupélien (—Stampien), 
instead of Latdorfien (=Sannoisien) as hitherto considered. The 
Polyzoa contained in them had already been described by Reuss, 
and of the seventeen species obtained by M. Canu by washing 
15 kilogrammes of the clay, fifteen had already been recorded by 
the former author. One new species is described and a new genus 
founded for one of Reuss’ species. 
The material of the other contribution was from the Marnes 4 
Huitres of Fresnes-les-Ruigis, of Stampien age, and is chiefly 
remarkable for yielding three recent species, from the occurrence of 
which M. Canu is led to the conclusion that ‘‘ Les marnes a Huitres 
de Fresnes-les-Ruigis paraissent s’étre déposées par 20 ou 25 metres 
d’eau au voisinage d’estuaires de petits cours d’eau”’ 
III.—Mesozorc anp Crnozorc Maorrina or rae Paciric Coasr oF 
Nort America. By Eart L. Pacxarp. Univ. California Publ. 
Bull. Dept. Geol., vol. ix, No. 15, pp. 261-360, pls. xii-xxxv, 
MOTO. 
HIS memoir is based on the study of a large number of fossil and 
living Mactrine from North American: Pacific Coast regions 
between Mexico and Alaska, belonging to the Universities of California 
and Washington. The author adopts the taxonomic system proposed 
for these molluscs by Dr. W. H. Dall during 1889 and subsequent 
years, in which was emphasized the importance of the Pelecypod 
hinge-structure for purposes of classification. In discussing the 
various elements of the Mactrine shell attention is directed to its 
general shape, the position of the beaks, the type of the pallial line 
with its sinus, the muscle-scars, and the dental armature. Form- 
variation is illustrated by a series of ‘eraphs’ showing ratios of lengths 
to heights. Contours vary from a trigonal to an elongate type, their 
many “variations having been observed to exist within the limits of 
certain species, while ‘others are much more constant. Systematic 
descriptions are given of the different species represented, under the 
genera Mactra, “Mulinia, and Spisula, these being divided into 
a number of sub-genera and sections. Those species recognized as 
new to science include Spisula brevirostrata and S. mercedensis 
(Pliocene); Mactra trampasensis, Mulinia pabloensis, and Spisula 
