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Show INSECTA. 320 discovered the two othet'S in the same Insect. They are situated, as in other Diptera, near the origin of the halteres. The abdomen of the Hippobosca ovina-see Mclophaguspresents ten in the form of little round, corneous, umbilicated tubercles, the four last being approximated to the anus. Those of the thorax, always four, are very ap1)arent. According to the same observer the interior .of this part of the body in the H. eq'Uina presents both utricular and tubular trachere ; but those of the abdomen are all of the latter de-scription and very num~rous. The wings are always distant and accompanied by hal teres. Their edge is more or less fringed with cilia. The superior nervures which are in its vicinity are str~ng and very distinct; but those which then extend to the posterior margin are but slightly marked and are not united transversely. In the last Diptera of this family, these organs are wanting or are merely rudimental. The halteres also disappear. The legs are very distant and terminated by two robust nails with one or two teeth beneath, which makes them appear double or triple. The skin of the abdomen is formed of a continuous membrane, so that this part of the body is susceptible of being distended and of acquiring a considerable volume, as necessarily happens in those female Hippoboscre, where the larvre are hatched and continue to reside until the period of their trans· formation into pupre. At this epoch the larvre issue from the venter of the mother in the form of a soft, white egg, almost as bulky as the maternal abdomen; the skin hardens and becomes a firm shell, at first brown, then black, round, and frequently emarginated at one end, and presenting a glossy plate or operculum which is finally detached in the manner of a cap to allow the egress of the perfect Insect. This shell has no annuli or transverse incisures, a character which distinguishes it from the other pupre of Diptera, and from those of the Athericera particularly, to which it approximates the most. It is to the splendid Memoirs relative to these Insects by Reaumur, De Geer, and M. Leon Dufour, all accompanied by detailed figures, that we must recur, in order to obtain a DIPTERA. 321 pro·f ound knowledge of the se t ransformaf nation of the changes which take . wns, and an expla-moment of depositing her I place In the female at the has surpassed his predecess:rv~ The la~ter, ~n particular, which have unveiled some ~~ hyl a~atomw~l Investigations £ t h tg Y mterestmg and . ac s.. sue as the existence of sa 1I. v ary gland f curious matrtx(l) consisting of a lar e s, o a sort of adapted for gestation and a 1 ' musculo-membranous pouch and of ovaries entirely di.m na ogtofus to the uterus of woman, T ueren rom those of th I hese ovaries consist of tw b . o er nsects. a white homogeneous pulp fo o tusde, ovmd bodies filled with . ' ree an rounded at . and termmating at the oth . . one extremity to this anatomist these ov e_r In la pecuhar duct. According ar1es c osely ap · woman in their form and . . proximate to those of position • Rea u h d . of them. The matrix' wh·I c h a t fir' st I.s vmeru r a 11a gbh mpse progress of gestation becom y sma ' y the b es enormously d.l t d ack the viscera and finall . d I a e ' pushes abdo~en, which' is thus re~:~:: :::;~;:~le c.;.~ity of t~e of this able observer rese . . e memmr as they differ but little~ if a~~l~t~er Interestin~ facts, which, shall not stop to analyze. ' rom the ordmary laws, we These Insects, which have been called b Mouches-.!lraignees ' live excl us.t ve I yon Qu adryu pseodm e aBut.h odr s run very fast, and frequent} Y S.I de ways. s or Ir s, Some-Coriaces, Lat -(2) h .. ticulated with the ante .' av~ a very distmct head ar. form the genus riOr extremity of the thorax. They HIPPOBOSCA, Lin. Fab. ( 1) Professor Nitzsch, who in his M • . . genera of Pupipara, mentions t ~mOir on EpiZOIC Insects treats of various but he neither alludes to this m:o. ovaries and fou.r biliary vessels in Hippobosca, (2) Doctor Leach has pub I' h : nor to the sahvary glands. excellent figures beautifull lS e a Monograph of these Insects, enriched with V IV, Y engraved. OL. .-2 Q |
