INSECTA. I 1!) 



nerve to the pigment, forming the pupils. The author 

 thinks that they are motory filaments, and serve for the 

 dilatation and contraction of the pupil. J. Miiller has 

 called attention, in a note, to the remarkable structure of the 

 dilatations of the fibres of the optic nerve of the river Crab. 



INSECTA. Leon Dufour (Ann. d. Sc. Nat. xix, p. 147, 

 pi. 6-9; Fror. N. Not. vol. xxvi, p. 257) has furnished a 

 comprehensive memoir on the Malpighian vessels of Insects, 

 in which he gives a copious review of the various forms of 

 these organs, in the different orders, with numerous figures. 



The author expresses himself iii favour of the view which ascribes to 

 these organs the function of secreting bile, and, in proof of this, relies 

 chiefly on the circumstance of their opening into that part of the intestine 

 in which the chyle is prepared. The correctness of this view might have 

 received still farther confirmation from a reference to the great analogy exist- 

 ing between the Malpighian. vessels of the Locust, aiid the liver of the Crab. 

 Neither has the author entered into the more minute structure of the organs 

 in question. Leaving out of view the cases (in a great many Coleoptera) 

 in which a second insertion of the Malpighian vessels into the rectum seems 

 to take place, the author found, in many Hemiptera, that these vessels appear 

 to open into a special sacculatcd enlargement of the rectum, but upon more 

 accurate examination he was convinced that these pouches belonged not to 

 the rectum, but to the preceding portion of the intestine, which in Astemma 

 (Pt/rrhocoris) apterum presented even a whole series of preceding csecal 

 pouches. 



Goureau has made the iridescence of the wings of Insects 

 the subject of his researches, and shown that it is almost 

 always presented, in a greater or less degree, by the trans- 

 parent, and not unfrequently also by the coloured wings. 

 He refers it to the physical phenomenon of the spectrum. 

 (Ann. d. 1. Soc. Eut. d. Fr. 2. Ser i, p. 201.) 



V. Siebold has continued his inquiries respecting the occurrence of Filariee 

 in the Lisecta. (Eut. Zeit. s. 78.) 



As works upon separate Faunas, are to be enumerated : 

 Esposizione sornrnaria delle osservazione raccolte durante 

 Fanno 1842 intorno allo sviluppo ed apparazione successiva 

 degli insetti nei contorni di Napoli, Di Achille Costa, in 

 the Annali dell' Accademia degli Aspiranti Naturalisti. 



