414 Notices of Memoirs — Mineral Industries of Vermont. 



the genus Lytoceras, but which are now separated into Lytoceras, 

 Gaudryceras, and Tetragonites. Upon Uhlig's group of Lytoceras 

 Sacya A. de Grossouvre founded the genus Gaudryceras ; from this 

 Kossmat separated two other types which he named Tetragonites and 

 Pseudophyllites, regarding all three forms as subgenera of Lytoceras. 



Pseudophyllites, so far as at present known, is represented by 

 only one species, P. indra. Naumann recorded from the Hokkaido 

 a new species allied to F. indra, but according to Professor Yokohama 

 the specimen is much too fragmentary for specific determination, and 

 unfortunately the collection made by the author did not include an 

 example of the species. 



Lytoceras, s. str., is represented by two species, both of which 

 are new. 



Gaudryceras can be divided into two well-marked sections, the 

 one containing G. Agassizianum and G. Marut, the other being 

 the group of G. Sacya. All the species of Gaudryceras are very 

 imperfectly known. " This," says the author, " is partly due to 

 the fact that, although they are very common especially in the 

 Upper Cretaceous deposits of the Indo-Pacific region, the specimens 

 usually belong to immature animals, and consequently closely 

 resemble one another, so that the determination is not only very 

 difficult, but often quite impossible. Moreover, the aspect of the 

 -shell of this genus is so different in its younger and older stages, 

 that without a large series of specimens for comparison, the larger 

 and smaller forms are often liable to be separated into distinct 

 species." All the Gaudryceras from the Hokkaido belong to the 

 group of G. Sacya, which the author subdivides into six subgroups, 

 based mainly upon the character of the full-grown shells ; four new 

 species and a number of new varieties are described. 



In the genus Tetragonites, besides the species described by Jimbo 

 as Lytoceras glahrum and recognized by Kossmat as belonging to 

 this genus, the author places Professor Jimbo's Lytoceras sphceronotum 

 and Zyt. crassum. 



Judging from the figures and the detailed observations which the 

 author has been able to make on some of the species, it seems that, 

 like the fossils from the Upper Cretaceous rocks of Southern India, 

 the specimens are exceedingly well-preserved. 



We most heartily congratulate the author upon his work, and 

 hope ere long to have the pleasure of seeing a further portion of 

 his memoir. G. C. C. 



II. — Eepokt of the State Geologist (George H. Perkins) on 

 THE Mineral Industries and Geology of certain areas of 

 Vermont, pp. 191, with 64 plates. Albany, New York, 1902. 



rPHIS volume, for 1901-2, is the third of the series issued by the 

 JL present State Geologist. It includes biographical sketches of 

 two old Vermont geologists — Zadock Thompson (1796-1856) and 

 Augustus Wing (1808-1876) — and gives a bibliography of the 

 official and other publications relating to the geology of the State. 

 The only mineral products of any economic importance are asbestos 



