226 INSECTA. 



t 



apparatus, intestinal canal, biliary vessels, also called hepatic 

 vessels, those styled salivary, but which are less general, free 

 and floating vessels called excrementitious, the epiploon or 

 corps graisseux, and probably of the dorsal vessel. This sys- 

 tem is singularly modified according to the difference of the 

 aliment, or forms a gre^it number of particular types, of which 

 we shall speak when treating of families. We will merely 

 say a word with resp«ct to the buccal apparatus and the prin- 

 cipal divisions of the intestinal canal, beginning with the lat- 

 ter. In those where it is the most complicated, as in the 

 carnivorous Coleoptcra, we observe a pliarynx, oesophagus, 

 crop, gizzard, stomach or chylific ventricle, and intestines 

 which are divided into the small intestines, great intestine or 

 caecum, and the rectum. In those Insects where the tongue, 

 properly so called, is laid on the anterior or internal face of 

 the lip. or is not free, the pharynx is situated "on that same 

 face, and this is most commonly the case(l). We will also 

 add, that a naturalist who first furnished us with correct ob- 

 servations on the respiratory organs of the Mygales, M. Gaede, 

 professor of natural history at Liege, does not consider the 

 biliary vessels as secreting organs — this opinion, however, 

 does not appear to be sufficiently well founded, and the ob- 

 servations of M. Leon Dufour(2) even seem to destroy it. 



Some few, and always apterous Insects, such as the Myria- 

 poda, approximate to several of the Crustacea, either in the 

 number of the annuli of their body and in their legs, or in some 

 points of analogy in the conformation of the parts of the mouth ; 

 but all the others never have more than six legs, and their body, 

 the number of w^hose segments never extends beyond twelve, 

 is always divided into three principal parts, the head, trunk 

 and abdomen. Among the latter Insects, some are found 



(1) See what we have stated respecting the llgula, In our general remarks on 

 the three classes. 



(2) This latter naturalist, whom I shall have frequent occasion to mention, has 

 published, with the most minute detail, every thing- relative to the digestive sys- 

 tem of Insects, in a series of admirable Memoirs, which have enriched tlie Annales 

 des Sciences Natiirelles. A well arranged resume of the whole by M. Victor 

 Audouin may be found in the Diet. Class. d'Hist. Nat., article Insectes. 



