REPORT ON ZOOLOGY. 209 



(Vespa Crahro, Linn.) being selected as the type. I am not 

 aware that this second monograph has been yet published*. 

 During the same year an elaborate memoir appeared in this 

 country by Mr. MacLeay on the structure of the thorax in winged 

 insects, in which he has not only given the result of his own 

 inquiries, but reviewed the previous labours of Audouin and 

 Kirby on this subject, especially the nomenclature of the dif- 

 ferent parts of the thorax as assigned by these authors respec- 

 tivelyf. Lithe Annales des Scien. for 1832J:, is a memoir by 

 Duges on the structure of the genus Pulex, with the particular 

 view of discovering its true affinities. This genus constituting in 

 itself an entire order of insects, the memoir is of considerable im- 

 portance. In the Entomological Magazine^, Mr.Westwood has 

 also made some remarks on these insects more particularly relating 

 to the structure of their antennae. In the Notiv. Ann. dti 3Ii(s. 

 for the same year||, Latreille has published a valuable memoir 

 on the external structure and affinities of the Thysaniira, which 

 his researches lead him to think form the transition from the 

 Myriapoda to the true Insects. They are the only insects in 

 which Latreille has not been able to discover stigmata ; the ab- 

 sence of which he regards as one of the distinguishing charac- 

 ters of this order^. Lastly, I may refer to some papers by Mr. 

 Newman on the external anatomy of Insects in general, recently 

 published in the Entomol. Mag** Latreille has also treated of 

 the whole subject in his Cours d'Entomologieff. 



It would be out of place to dwell much on the internal ana- 

 tomy of insects in this Report. I shall do little more than ob- 

 serve that it is principally to the researches of Marcel de Serres, 

 L^on-Dufour, Duges, and Straus-Durckheim in France, and to 

 those of Herold, Gaede, CarusJI, Suckow, Meckel, and Miiller 



• An analysis of it will be found in the Bull, des Sci. Nat. for 1 830, (torn, 

 xxii. p. 347,) also in Cuvier's Analyse des Travaux for the same year. 



t Zool. Journ., vol. v. p. 145. J torn, xxvii. p. 145. 



§ vol. i. p. 359. II torn. i. p. 16'l. 



1[ The Thysaniira have been sadly neglected by entomologists. Latreille 

 observes that with respect to the Poduree there has appeared nothing new since 

 the time of De Geer. ** vols. i. and ii. 



tt I may state in this place that two general introductory works on entomo- 

 logy have appeared recently which I have not seen, both entering into details 

 on the subject of the organization of insects. One of these is the Handbuch 

 der Entomologie, published by Burmeister at Berlin in 1832. The other is the 

 Introduction a l' Entomologie by Lacordaire, of which the first volume has only 

 just appeared. See L'Insiit., No. 73, p. 324. 



XI Carus has the particular merit of having discovered the circulation of the 

 blood in Insects. This remarkable fact, which was observed in the lai-vae of 

 certain Neuroptera, was first announced at the meeting of German naturalists 

 held at Dresden in 1826. 



1834. P 



