INSECTA. 341 



long, setaceous antennae, they (the antennae) are organs of touch, 

 it seems to us difficult to account for the extraordinary development 

 they acquire in certain families, and more particularly in the males, 

 if we refuse to admit that they are then the seat of smell. The palpi 

 also, in some cases, as when they are greatly dilated at the extremity, 

 may possibly be the principal organs of smell, part of which sense 

 may also perhaps belong to the ligula. 



The digestive system consists of a preparatory or buccal appara- 

 tus, intestinal canal, biliary vessels, also called hepatic vessels, those 

 styled salivary, but which are less general, free and floating vessels, 

 the epiploon or corps graisseux, and probably of the dorsal vessel. 

 This system is singularly modified, according to the difference of the 

 aliment, or forms a great number of particular types, of which we 

 shall speak when treating of families. We will merely say a word 

 with respect to the buccal apparatus and the principal divisions of 

 the intestinal canal, beginning with the latter. In those where it is 

 the most complicated, as in the carnivorous Coleoptera, we observe 

 a pharynx, O3sophagus, crop, gizzard, stomach or chylific ventricle, 

 and intestines. 



Some few, and always apterous Insects, such as the Myriapoda, 

 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 whose 

 segments never extends beyond twelve, is always divided into three 

 principal parts, the head, trunk and abdomen. Among the latter 

 Insects, some are found without wings, that always preserve their 

 natal form, and merely increase in size and change their skin. In 

 this respect they bear some analogy to the animals of the preceding 

 classes. Nearly all the remaining Hexapoda have wings; but these 

 organs, and even frequently the feet, do not make their appearance 

 at first, but are only developed after a series of changes, more or 

 less remarkable, styled metamorphoses, of which we shall soon 

 have to speak. 



The head bears the antenna;, eyes, and mouth. The composition 

 and form of the antennae are much more various than in the Crus- 

 tacea, and are frequently more developed or longer in the males than 

 in the females. 



The eyes are either compound or simple; the first, according to 



