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Show 318 . INSECTA. . f h'ch we 11 ave h1.therto spoken, we have In the D1ptera o w 1 h per·10. d 'nto t e su r canal of a tubular found a sucker rece1ve 1 geniculate at base, most 1 s membranous, . 1 . sheath, more or. ets d by two 1t' ps, a nd accoropamed by pa pt. frequently termma e . he last subgenus or Phora, have The antennre, except ~n t d ar the front. The larvre always appeare d to be mserte ne tible of be.m g hateh ed m. of these Diptera, although l~uscepbroad and feed on various f th mother, lVe a d the venter o e . 1 These Insects have forme substances, vege table o. r ammha' ·h 's divided into five f:a m·t1t·e s. 1 sectiOn w 1C 1 d . our first genera . w • ll these respects an m some h d d1uer 1n a . Those of t e secon 1 d this dissimilarity has even others t h at are less genera. c ' an the latter into a parti.c u1 a r D t Leach to 1orm . . induced oc or Those which termmate tt, h t f 0MALOPTERA. • order, or t a o . of win sand halteres, have a certam and which are destitute d gd Aptera that compose our . h th Hexapo a an affinity Wlt e . he enus Pediculus of Linnreus. order of the Parast~a or :ll ~ g our last family of the Diptera. This second section W1 orm FAMILY VI. PUPIPARA. H' boscre were distinguished These Insects, at least the tppo lla;ion of Nymphipa1·a. by Reaumur, under the analogo~s app~ divided into two dis· Their head, viewed from a. ove, :more particularly com· . ts One posteriOr, an . h t1nct arere or par . . . . t the eyes and receiVeS t e Posing the head, gtves ortgm o. t' The latter is also · nterior emargma 10n. othel' part tn an a . lar e and coriaceous, divided into two portion~, th~ poster~o:he ~ther constituting bearing the antennre on Its. Sl es,..;:e inferior and oral cavity the apparatus of roan.ducatiOn. mbrane • from its extremity of the head is oc?~p1ed by a ml' e 1 b lb' or projecting pediissues a sucker arlstng from a Itt e u DIPTEUA. 319 cle, composed of two closely approximated threads or setre, and covered by two coriaceous, narrow, elongated, and pilose laminre which form its sheath. Whether these laminre or valvulre represent (as I presume) the pal pi of other Diptera, or whether they be parts of a true sheath, as is the opinion of M. Dufour in speaking of a species of Ornithomyia-Ann. des Sc. Nat., X, 243, XI, 1-where he has discovered two little bodies which he considers as pal pi( I), it is not less a fact that the proboscis of these Insects evidently differs from that of the preceding Diptera, and that the sheath, in this case, would be more analogous to the proboscis of the Flea, from which however it is removed by the absence of articulations. The body is short, tolerably broad, flattened and defended by a solid skin almost of the consistence of leather. The head is more intimately united to the thorax than in the preceding families. The antennre, always situated at the lateral and anterior extremities of the head, sometimes form a tubercle hearing three setre, and sometimes little hairy laminre. The eyes vary as to size; in some species they are very small. M. Leon Dufour, in his description of the Ornithomyie bilobee, has observed that although this genus has had ocelli attributed to it, he has not been able to discover them. A fresh examination of such species as I could procure has in fact convinced me that we were mistaken(2), and it may be considered as a general rule that the Pupipara are destitute of those organs. The thorax presents four stigmata, two anterior and two posterior. The learned entomologist just referred to, in the Hippobosca equina of which he has described the Anatomy-Ann. des Sc. Nat., VI, 299, et seq.could only find the two first, those which are situated on the lateral and anterior extremities of the mesothorax; but I have (1) In the Melophagi, the base of the lamina: of the sucker is covered by two little coriaceous, triangular and united pieces, forming a sort of labrum. They seem to form a miniature representation of the two pieces that cover the base of the proboscis of the Flea. (2) Dr Leach, however, admits that they exist in certain species. |
