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Show I I 36 INSRCTA. The second section of the Hemiptera, that of the H OMOP· TERA, Lat., is distinguished from the preceding one by the following characters : the rostrttm arises from the low?st portion of the head, near the pectus, or even fr~m the mtcrval between the two anterior legs: the elytra-almost always tectiform- are of the same consistence throughout and semimembranous, sometimes almost similar to the wings. The three segments of the trunk are united en masse~ and the first is fr·equently shorter than the second. All the Insects of this section feed exclusively on vegetable juices. The females are. provided with a scaly ovipositor(!), usually composed ~f three dentated blades, and lodged in a groove with two valves. They use it as a saw to produce openings in plants in which they deposit their eggs. The last Insects of this section experience a sort of complete meta· morphosis. I will divide it into three families. FAMILY I. CICADARI.lE. This family comprises those which have triarticulated tarsi, and usually very small, conical, or fusiform antennre, com· posed of from three to six joint'3, the extremely attenuated seta which terminates them included. The females are pro· vided with a serrated ovipositor. MM. Randohr, Marcel de Serres, Leon Dufour, and Straus, have studied the anatomy antenna: is lnrger than the others, and because those of the anterior tarsi are almost of the same length, and the hooks of the posterior ones are large. The body is shorter, and the elytra entirely crustaceous, arched, and truncated at the exterior angle of their base. A piece is observeu there, analogous to that remarked in the same place in the Cctonire. (1) Called oviscapte by M. Marcel de Serres. IIEMlPTERA. 37 uf several Insects belonging to this family. The latter naturalist has not yet published the result of his investigations. The researches of M. Dufour are the most extensive and complete, at least so far as respects the digestive system and the organs of generation. A proof of this is readily obtained by referring to his Memoir entitled Recherches .llncdomiques sur les Cigales, inserted in the fifth volume of the Annales des Sciences N aturelles. We will not follow this profound observer into the multitude of interesting details respecting their organization which he pre~cnts to us, and which he accompanies with excellent figures, but restrict ourselves to the description of an anatomical character which appears to be exclusively peculiar to these Insects. In all of them, according to him, the chylific ventricle or stomach is remarkably long; it commences by a curved or straight, oblong dilatation, and always terminates in an intestiniform canal, which is flexed 'on itself in order to arrive at the origin of this same ventricle, into which it opens by the side of the insertion of the hepatic vessels, not far from the. commencement of the intestine; they all have four biliary vessels. In the Cicadre this ventricle has the figure of an ear, of which the right side is dilated into a large lateral and frequently plaited pouch; its upper extremity is tied to the esophagus by a superior ligament, and the other leads to this narrow, very long, tubular, reflected prolongation which has the form of an intestine, and which, after these circumvolutions, reascends to join that pouch near the insertion of the hepatic vessels. This singular disposition of the chy1ific ventricle which after several convolutions empties into itself, in continuing a complete circle traversed by the alimentary liquid, is doubtless a difficult matter to explain physiologically, but it is not the less a well determined and constant fact, and one which forms the most characteristic trait in the anatomy of the Cicada and other' Cicadarire. In the Ledra aurita of Fabricius, or Procigale Grand-diable of Geoffroy, the inflated portion of the chylific ventricle is placed directly after the crop, and there is but a single cluster of salivary sacs on each |