141 



some silk threads by the tail, throwing a few others across the body, and spinning a very 

 thin, transparent, loose cocoon between the leaves. Another chapter is devoted to the 

 " Special Classification of the Lepidoptera," in which the butterflies are asserted to be at 

 the head of the order (and consequently the most highly organized of all the Annnlosa), 

 because they sit with their wings erect, the inner side in the pupa state becoming the 

 outer one, whereas the Hesperidse raise the anterior wings only, and stretch the lower 

 ones more or less horizontally ; while Sphinges and moths sit with those organs more 

 or less in the position they assumed in the pupa state : the precise method of spreading 

 the wings in repose being considered as the first character to be employed in the clas- 

 sification of the families of heterocerous Lepidoptera. 



M. E. Blanchard read a Memoir before the Academie des Sciences, on the 6th of 

 October, 1851, on the Circulation of the Blood and on the Nutrition of Insects, with a 

 view to explain why silk-worms, fed upon leaves powdered with coloured matters, pro- 

 duced similarly coloured silk ; and in order to demonstrate the correctness of his views 

 as to the peritracheal circulation in insects. (Rev. Zool. 1851, p. 492; and Ann. N. 

 Hist. January, 1852). 



M. Joly has published a Memoir on the asserted Peritrachean Circulation, (Ann. 

 Sc. Nat. 3rd ser. xii. p. 306) ; in which he insists that it is physically, anatomically, 

 and physiologically impossible. 



On the other hand, M. Agassiz, in a Memoir on the Circulation of Blood in In- 

 sects, read before the American Association for the Advancement of Science, in 1850, 

 adopts the peritrachean system of circulation. 



A Memoir by M. Quatrefages, on the General Cavity of the Body of Invertebrated 

 Animals, and on the Liquid contained therein, and its functions, has been published. 

 (Ann. Sc. Nat. 3rd ser. xiv.) 



A paper on the formation and use of the Air-sacs and dilated Tracheae in Insects, 

 by Mr. G. Newport, appears in the ' Transactions of the Linnean Society,' xx., pt. 3. 



A curious memoir by Dr. Hollard, on the Structure of the Scales, Hairs, and other 

 appendages of the Skin of Articulated Animals, has appeared in the ' Revue Zoololo- 

 gique/ 1851, p. 283. 



The 6th part of the ' Proceedings of the Literary and Philosophical Society of Li- 

 verpool' contains an elaborate paper on the Structure of the Feet of various species of 

 Insects of different orders, with highly magnified figures, by Dr. Inman. 



A paper by Professor L. Agassiz, on the Numerical Composition of the Segments 

 of the Body of Larvae, perfect Insects, and Crustacea, appears in the ' Proceedings of 

 the American Association for the Advancement of Science,' for 1850. 



A remarkable memoir by M. F. Dujardin, has appeared (Ann. Sc. Nat. 3rd ser. 

 xiv.), in which the author asserts that there is a true brain in some insects, the struc- 

 ture and size of which depend on the development of their intellectual faculties ; this 

 true brain being surrounded by a cortical pulpy substance, which is of small extent in 

 the more intelligent insects, but predominates in those in which intelligence is masked 

 by instinct : the ganglions of the thorax and abdomen appearing to be exclusively com- 

 posed of this pulpy cortical matter. 



M. E. Perris, having reviewed the various opinions proposed on the subject of the 

 seat of the sense of smelling in articulated animals, considers that it chiefly resides in 

 the antenna?, and also, to a certain exteut, in the palpi ; and further, that the antennae 

 are not organs of hearing, the seat of which is placed in the cavity in which the an- 

 tennie are inserted. (Ann. Sci. Nat. 3rd ser. xiv. p. 149). 



