vfdan, T^ift wew* of M. Geofioy wiil probably b« modified by th» »rfivri of 

 a^otheir aocpdile, also embalmed, larger, axid in some respects very di£&reQt from 

 (he a])ecitneB given to the Jardiu du Roi by M. Calliaud. 



Robineau d«s Voidy, on, the Gewus Musca. — ^Nothing proves more clearly the 

 immense progress of which natural history is always susceptible in many of its 

 l^aacbes, than the memoir presented to the Academy by M. RobiDcau dea Voi' 

 dy, on the insects which compose the genus Musca of Fabricius. 



The genera of knowa dipterous insects amounted only to ten in the 1 2th edition of 

 the Syslema Natura ; but in sixty years the successive researches of Fabriciiw^ 

 ^treille, and other entomologists, have produced a rapid increase in their num^ 

 b«rs. Fabricius hrovjgiit them up to 23, JUatyeille to 117, and Meigei) to nearly 

 400. 



Al. Kobineau has occupied himself with a single genus only of Fabricius, to 

 which the entomologist of Kiel had appropriated the name of Musca ; and he 

 has observed and collected nearly 1800 species, of which more than 1400 are 

 new. But what is mo^ remarkable, and may give us a more exalted idea than 

 we ever possessed of the prodigious riches of nature, is, that most of these species 

 have been collected in a very limited canton of a single department, that of the 

 Yonne. The points of view under which he has considered the delicate peculia- 

 rities of organization, which he has observed in every part, especially in the mouth, 

 in the forms of the head, and in the structure of the antennae, in the nerve* of 

 the wings, and in the disposition of the little scales placed under the base of the 

 wings, &c have led him to establish divisions and subdivisions of many degrees, 

 to which he gives the titles of families, sections, tribes, and genera; and he has 

 endeavoured to trace his subdivisions so as to embrace the species which are re- 

 lated not only by form, but also by habits, by the substances on wliich they feed, 

 and the places where they deposit their larvae. The genera which he establishes, 

 in the single genus Musca of Fabricius, which is itself only a dismemberment 

 pf the Musca of Linnaeus, amount to the astonishing number of nearly 600 ; 

 that is to say, to nearly seven times as many as Linnasus had established 

 for the whole class of insects ; he gives only 86 in his. last edition. After this 

 remark, it will be conceived how impossible it would be for us, without much ex- 

 ceeding the customary extent of our analyses, to give any idea of such a complicat- 

 ed work. 



Dejean on the Carabi and Cicindelae — rA similar multiplication of species has 

 taken place with the insects known under the names of Carabi and Cicindela^ 

 in the great work oi M. Dejean. These names were given by Linnaeus to coleop- 

 iera whose nu)tions are rapid, whose jaws are prominent, siiarp, dentated, and 

 •furnished with palpi, and whose habits are cruel and carnivorous. They con- 

 stituted t>vo of the 86 genera of his class of insects, and in his last edition l)Oth 

 of them contained only 57 species. This number has been successively increased 

 fey the labours of entomologists, and especially of JJL Bonnelli ; and ]\L Latreille 

 in his last work, " Les FamUles du Regne Animal,'''' had already discovered 

 sufficient characters to divide them into 97 gen«^ra. At present, the collection of 

 M. Dejean alone, certainly one of the richest in coleopterous insects, contains 

 nearly 2000 species, and the detailed characters which this learned entomologist 

 -has recogniiied in these inmaense numbers, have led liim to distribute them into 

 & tribes, subdivided into many genera. The iirst four tribes alone, described in 

 the two first volumes of the work, contain 70 genera. This work does not only 

 offer a classification as exact as the state of science will admit ; but also contains 

 descriptions of all the species, sufficiently detailed to induce the hope that the 

 nomenclature is fixed as surely as it is possible without figures : figures even 

 'would not suffice, if they were not performed by the best artists, and if they did 

 not represent the object under every aspect. 



Mongez on the original habitat of the Mulberry Tree — Every one knows that 

 the silk, which is the source of so much industry, and the means of so many 

 agreeable and useful employments, did not originally come from the country 

 VOL. II. 3 C 



