402 NOTICES OF NEW BOOKS. 



contrary, we find species, such as the Aphides, which in the tropics 

 are represented by other and much larger insects, associated with 

 Libellulce (dragon-flies) of gigantic size, and other species nearly 

 allied to the almost equally voracious insect-feeding genera, 

 Pa7iorpid<e. 



" It is scarcely to be supposed," adds Mr. Westwood, " that a 

 state of things could have existed in which we should find such a 

 collection of insects as the Wealden series exhibits, without there 

 being parts of the world inhabited by giant Cicadce, immense 

 beetles, locusts, and grasshoppers, with wings expanding little less 

 than a foot, and other insects of the size at least of those in the 

 present creation." 



The number of families and genera determined from the Wealden, 

 so far as the condition of the specimens would allow, is very 

 considerable. Thus there are 18 Coleoptera, 3 Orthoptera, 12 

 Jlemiptera, 7 Neuroptera, and 13 Diptera ; but some of the num- 

 ber are very imperfectly made out. 



IV. Kosmos. Entwurf einer physischen Weltbeschreibung* 

 Von Alexander von Humboldt. Erster Band. Stuttgart 

 und Tubingen. 1845. 8vo., pp. 494. 



This first volume of a work under the title of " Cosmos " (or the 

 Universe), vast and comprehensive in its object, and undertaken by 

 that remarkable man who has made such important and valuable 

 contributions to the scientific literature in Europe — Alexander 

 von Humboldt — has been long expected on the continent, and 

 naturally excites very considerable interest among a large class of 

 , persons who are carefully working out in detail one department of 

 science, and are at the same time anxious to obtain the best and 

 truest general views concerning the progress and present condition 

 of other branches, and of the connection that may be traced 

 amongst them. M. de Humboldt's essay will be read and studied 

 by such readers, and will no doubt be long quoted as a text^book 

 even when the advance of knowledge and general views in science 

 shall have rendered it out of date. Translations of it are, we 

 know, preparing in our own and in the French language, and these 

 will soon make the Cosmos familiar to all. Meanwhile, we will 

 endeavour to give in a very few pages a general outline of the 

 work, and more especially of that part of it which is technical to 

 ourselves, as introducing the subject of Geology. 



The volume now before us contains : — 1. Preliminary consider- 

 ations concerning the extent and variety of the different kinds of 

 enjoyment arising from the study of nature and the investigation 

 of nature's laws. 2. An account of the limits and the scientific 



* Sketch of a physical description of the universe. 



