go NATURAL SCIENCE. August. 



Science in Mexico. 



We have received La Natumleza, the publication of the Mexican 

 Society of Natural History, for 1893-95. This consists of five parts, 

 being nos. 5-g of vol. ii. of the second series, and gives one a good 

 idea of the activity of naturalists in Mexico. 



In zoology, Dr. A. Duges has an interesting paper on the colour 

 variation of the lizard Gerrhonotiis imhricatus, and illustrates his obser- 

 vations with a coloured plate. In another paper he describes the 

 footprints of a mammal of the genus Felis from the Upper Pliocene or 

 Pleistocene deposits of Verdolaga. The impressions correspond 

 closely with those made by the recent F. concolor. Some footprints of 

 birds found with the Felis are referred to Oxyechus vocifenis. Professor 

 Herrera concludes his valuable memoir on the climate of the Mexican 

 Valley and the biology of vertebrates, and gives a chart showing the 

 range in height of mammals, birds, reptiles, and batrachians. The 

 paper is of considerable value to the student of geographical dis- 

 tribution. 



In geology, Dr. J. N. Rovirosa writes on the structure of the 

 Teapa Valley, and gives some notes on the Cocona Cave, which has a 

 length of 492 metres. Messrs. J. G. Aguilera and E. Ordoriez con- 

 tribute an explanation of a new geological sketch-map of the Mexican 

 Republic, which has been prepared under the direction of Dr. Antonio 

 del Castillo. The map accompanying the paper shows Quaternary 

 deposits round the greater part of the coast, and extending over a 

 large area of the country, especially to the north. Starting from the 

 Gulf of Mexico, and going west, we cross successively a narrow band 

 of Tertiary deposits, a broad area of Cretaceous, with here and there a 

 little Jurassic or Liassic, and reach the western half of the country 

 which is almost wholly composed of eruptive rock. A few patches of 

 cretaceous deposits occur, and some metamorphosed (Palaeozoic ?) 

 masses. Volcanoes, solfataras, and supposed extinct volcanoes are 

 shown. Ordonez has a note also on the composition of the Aztec 

 Calendar or Sun Stone of the City of Mexico. He finds it to be a 

 mass of Olivine Basalt (olivine, augite, labradorite, and magnetite), 

 and considers that the labradorite was the first to crystallise. A 

 micro-section of the rock is given. 



In botany, Mocino and Sesse continue the Flora Mexicana ; Dr. 

 J. Ramirez describes a new species of P. terostemon (P. rotnndifolia) ; 

 while Mr. P. Maurey describes Sehastiania ramirczii, a new Euphorbia. 

 Dr. J. N. Rovirosa writes a sketch of the life of E. P. Johnson, one of 

 the pioneer botanists in Mexico, and contributes a note on the Flora of 

 Tabasco. A list of ferns collected by Hugo Finck in the Cordoba 

 district, and sent to the World's Fair at Chicago, shows 149 species. 



Illinois and its State Geologist. 

 It is our occasional misfortune to have to call attention to the 

 eccentricities of writers, who, because they deal with scientific 



