#& INSECT A. 



counting the eight pairs of the brain, and the ten spinal bridles, which 

 may also be considered as so many pairs of nerves, we shall have in all 

 forty-five pairs, exclusive of two solitary nerves, or from twelve to 

 fourteen more than are found in the human subject. In our general 

 remarks on points common to the three classes of articulated animals 

 provided with articulated feet, we mentioned the various opinions of 

 physiologists with respect to the seat of the sense of hearing and of 

 smell. We will merely add, in regard to the former, that certain 

 little nervous frontal ganglions seem to confirm the opinion of those 

 who, like Scarpa, place it in the origin of the antennas. I have 

 detected two small orifices near the eyes of certain Lepidoptera, 

 which, perhaps, are auditory canals. If, in several Insects, parti- 

 cularly those furnished with filiform, or 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 apparatus, 

 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 it 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, 

 oesophagus, crop, gizzard, stomach, or chylific ventricle, and intes- 

 tines. 



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 ex- 

 tend beyond twelve, is always divided into three principal parts, the head, 

 trunk and abdomen. Among the latter Insects, some are found with- 

 out wings, that always preserve their natal form, and merely increase 

 in size and change their skin. In this respect they bear some analogy 



