fJ08 FOURTH REPORT — 1834. 



that already alluded to ; one on the supposed elytra of the Stre- 

 psiptera, and on the appendices of the trunk of Insects in gene- 

 ral* ; the other on the general relations of the external structure 

 of the articulated Invertebrataf. In 1821 Latreille published 

 a memoir containing further observations on the external struc- 

 ture of the Atinulosa, principally with a view to fix the nomen- 

 clature of the principal parts J. The same year appeared the 

 first of a series of elaborate memoirs by Chabrier on the organs 

 of flight in insects, with a detailed account of all the parts con- 

 tributing to the motion and articulation of the wings §. In 1825 

 an important memoir was brought forward by Mr. MacLeay on 

 the structure of the tarsus in the Tetramerous and Trimerous 

 Coleoptera of the French entomologists ||. Its object was to 

 show the defects of an arrangement founded on this part, and to 

 prove that such arrangement must necessarily lead to the viola- 

 tion of natural affinities. In 1826 appeared an elaborate dis- 

 sertation on the external anatomy of Insects in the third volume 

 of the Introduction to Entomology by Kirby and Spence. In this 

 work there is given a collected view of the researches of previous 

 naturalists on this subject ; at the same time there are some 

 material additions made to what had been already done by others. 

 In the Bull, des Set. Nat. for 1828, is an abstract of a memoir 

 by Haan on the organs of manducation and motion in the arti- 

 culated animals^!- It was during that year that Straus-Durck- 

 heim published his great work on the Comparative Anatomy of 

 the Articulated Animals **. This last is perhaps the most im- 

 portant and elaborate treatise of its kind that has hitherto ap- 

 peared. It is the first of a series of monographs which the au- 

 thor intends publishing on the structvire of the different orders 

 of insects. It contains some general remarks on the organiza- 

 tion of the Annulosa, after which the author proceeds to the 

 investigation of that of the Coleoptera in particular, the Melo- 

 lontha vulgaris being taken as the type. In the first part of his 

 subject, Straus-Durckheim has endeavoured to refer the different 

 modifications of structure which the organs undergo in passing 

 through different groups of articulated animals, to general laws. 

 In 1830 Straus-Durckheim read to the Royal Academy of Sciences 

 at Paris a portion of another work, treating in like manner of the 

 structure of the Hymenopterous Insects, the common Hornet 



• • Mem. du Mus., torn. vii. p. 1. f Id., torn. vi. p. 116. 



X Id., torn. viii. p. 169. § Id., tomes vi., vii., and viii. 



II Linn. Trans., vol. xv. p. 63. ^ torn. xiii. p. 443. 



•• Considerations generales siir V Analomie Comparee des Animaux ArticuUs, 

 auxquelles on a joint V Anatomie descriptive du Melulontha vulgaris (Hanneton), 

 donnee comme exemple de V Organisation des Coleopteres. Paris, 1828, 4to. 



