96 Geographical Distribution of Insects. 



it has appeared in the Edinburgh Philosophical Journal.* The 

 same subject was afterwards taken up by Macleaj^ in his 

 Horoe Entotiiologicce, and subsequently by Kirby and Spence, 

 in their well-known Introduction. Since that time, the study 

 of Entomology has been prosecuted with so much zeal, that 

 comparatively ample materials have been placed at the dis- 

 posal of those inclined to labom- in this interesting field. Of 

 these materials, perhaps, the most valuable is the well-di- 

 gested catalogue of Count de Jean, which determines, with as 

 much acciu'acy as the subject is susceptible of, the localities 

 of no fewer than 22,399 species.t These, it is true, are Cole- 

 optera alone, but aids of a similar description are not wanting 

 in most of the other orders. M. Lacordau'e, Professor of 

 Zoology in the University of Liege, is the last writer that has 

 availed himself of the numerous advantages which recent dis- 

 coveries aiFord for the illustration of this subject, to which he 

 has been enabled to add the result of his own personal obser- 

 vations, during a lengthened residence in many parts of the 

 new world, where his attention was particularly directed to 

 the inquiry. His essay we consider of so much value, in se- 

 veral respects, that we now propose to lay the substance of 

 it before our readers. While the direct object of it is to de- 

 termine the influences which seem to regulate the geography 

 of insects, many of the principles advanced will, we think, 

 tend to elucidate the distribution of animal life in general.| 



The geographical distribution of insects, like that of vege- 

 tables, may be considered under two points of view — 1st, in 



• See Vol. V. p. 370. 



+ This is the number included in the last edition of the Catalogue. Since 

 its publication, the collection has been increased to upwards of 23,000 

 species. It is, therefore, by far the richest private collection of Coleoptera 

 in the world. The species of the same order in the Berlin University Mu- 

 seum, the most extensive that exists, amounts to 28,000 species. 



X This essay is contained in an Introduction to Entomology, published 

 last year in Paris, forming a portion of the work entitled Siutes a Biiff<jn. 

 The first volume nay almost be regarded as a translation of Kirby and 

 Spence. The second contains an accurate abstract of the discoveries recently 

 made in insect anatomy, a department in which Kirby's work may be con- 

 sidered as already, in some degree, obsolete. The most original part of the 

 whole is the geographical essay in question. 



