PARTIAL ORISMOLOGY. 



The number of the joints of the antennae is tolerably regular, and 

 only varies in the different orders and families of insects ; but a few 

 only, as the Diptera pnpipara, have exarticulate, or one-jointed 

 antennae ; the majority of the rest of the Diptera, such as the true 

 flies (Muscaria}, and Syr phi, have THREE joints (see PI. VIII. f. 6 

 and 8 14, and 16 and 17). Just so is it in the genera Nepa and 

 Ranatra (PL VIII. f. 21), in the family of water-bugs (Hydro- 

 corides} ; while the remaining genera of these, as also of the field-bugs 

 (Geocorides), have POUR joints, with the exception of the five-jointed 

 genera, Pentatoma, Tetyra, and Reduvius. All the Cicadaria have 

 THREE joints, with the exception of Cicada, Lat. (Tetligonia, Fab.) 

 which has FIVE. The genera Asilus, Dioctria, Dasypogon, Hilara, 

 Empis, and Sargus, among the Diptera, have FIVE joints (PI. VIII. 

 f. 7 and 18). It is the same in the apterous flea (Pitlex), the lice 

 (Pediculi), and the genus Philopterus, among the equally apterous 

 parasitic skin-destroyers (Dictyotoptera mattopkaga). Two other 

 genera of this family, viz. Liotheitm and Gyropus, have but FOUR 

 joints; the fourth genus, Trichodectes, has but THREE. Six-jointed 

 antennae are rarely found, the genus Perga, and some species of the 

 genus Cimbex, among the Hymenoplera, display this number ; and 

 among the Diptera, the genera Hcematopoda, Hexatoma,Me\g. (Hep- 

 tatoma, Latr.), and Nematocera, Meig. (Hexatoma, Lat.). From SEVEN 

 to EiGHT-jointed antenme are found in other Diptera, in the genera 

 Stratiomys, Oxycera, Tabamts, Pangonia, Chrysops; but the last five 

 or six are so closely attached together, that they appear to form but one 

 joint. NINE joints are found in the hymenopterous genus Tenthredo ; 

 TEN in the approximate genus Athalia. ELEVEN-jointed antennae are 

 possessed by the Coleoptera, with a few exceptions ; for example, TEN 

 in Melolontha, Ori/ctes ; NINE in Copris, OniticeHus, Ateuchus, Apho- 

 dius, Geniates, Kirby; Plian&us, Leach (Lonchoplwms, Germar), and 

 many of their affinities; EIGHT, Dorcatoma and Calandra; FIVE, 

 Platypus and Claviger ; TWO, Paussus. IMore than ELEVEN joints 

 are found in some species ; for example, TWELVE in Cebrio gigas, 

 Chrysomela stolida, some Saperda, and the males of the genera 

 Stenochorus and Trachyderes. In Prionus imbricornis the female has 

 NINETEEN, and the male TWENTY joints ; Rhipicera marginata, Latr. 

 (Polytomus, Dalm.) has THIRTY-TWO joints ; Rli. femorata, TWENTY- 

 THREE ; Rh, mysticina, even FORTY. Among the bees, wasps, and the 

 other families of the Hymenoptera aculeata, the female has TWELVE, 



