24 



REPORT OF THE COMMISSIOIsER OF AGRICULTURE. 



HOMOPTERA. 



The suborder Homoptera of tbo order Ucmiptcra consists of insects 

 having four membranous- dellexed wings, usually lying over the back, 

 like the roof of a house, when the insect is at rest. The anterior pair of 

 wings are usually- larger tbau the posterior pair, generally transparent, 

 and net- veined. The mouth consists of a beak or sucker, which is used 

 to pierce the outer cuticle of plants they frequent, and to suck out the 

 sap in three of the stages of their existence. As larvae, puptc, and per- 

 fect insect, they are equally active and do much damage, feeding 

 almost entirely upon vegetable substances, and when very numerous, as 

 in the case of the ApJiidcs or plant-lice, they do much injury to vegeta- 

 tion by sucking out the sap, thereby weakening the plants, shrubs, 

 or trees they frequent. As no recent relia.ble catalogue of the Ho- 

 mojpiem has been published in this country, and only such old works as 

 Amyot and Serville, &c., can be referred to, it has been thought best 

 not to arrange these insects scientifically in this paper, but merely to 

 allude to some of those best known to our farmers, or to such as are 

 particularly distinguished by their destructive habits or singularity of 

 form. This suborder has been very much neglected by our entomolo- 

 gists, who usually take more interest in the study and collection of the 

 Coleoptera, (or beetles), and Lepidoptera, (butterflies, moths, &c.,) in 

 preference to the smaller and more inconspicuous insects, although the 

 Homoptera contain some of the most grotesque and singularly-formed 

 insects we usually meet with, such as Entilia, Telamona, Ceresa^ and 

 many others, which will bo found described and figured in a later part 

 of this report. We will therefore commence with the Cicadidcc, or har- 

 vest-flies, incorrectly knov/n in this neighborhood and elsewhere as 

 locusts; the real locust being an orthopterous insect, very closely allied 

 to our common grasshopper. 



The harvest-flies are largo insects, having a broad, short, transverse 

 head, with large prominent eyes, and broad thorax. The upper wings are 

 rather narrow, membranous, and deflexed over the sides of the body, 

 like the roof of a house. Oar most common species in this neighbor- 

 hood ia the Cicada xiruinotia, which 

 may be heard ia summer and autumn 

 at almost any time making its peculiar 

 trilling noise in the shade and forest 

 trees in the grounds of tbo Smithso- 

 nian Institution. These insects are 

 quite large in size, some of them 

 measuring 2 inches or more from tbo 

 front of the head to the tip of the 

 closed wings. The males alone are 

 musical, hence an old cynical writer 

 observes : " Happy the cicadas' lives, 

 since they all have voiceless wives." 

 The musical apparatus producing the 

 peculiar prolonged trillujg chirp or cry 

 made by the male is situated on the 

 under side of the body, on the basal 

 ring of tlic abdomen, and consists of a pair of largo i)lates, largely 

 covering the anterior part of the body, which, acting like a drum, at 

 the will of tbo insect produces the prolonged tremulous sound we 

 hear so often in the tops of the trees they inhabit ; if the tree on which 



