SUCTORIA. 489 



foiiniled with the abdomen, and the fuur hind le;;s very robust. {See Dr. Ahbert's fine work upon tlie maladies 

 of tire skin.) 



Other species, found upon diflerent quadrupeds, have been figured by Redi, but in a coarse manner. Ttiat which 

 lives upon the Pig has the thora.x very narrow, with the abdomen verj' broad {Pediculus i-luiny Linn., forming Leach's 

 genus tliematopinua). The Louse of the Buffalo, figured by De Geer {Ins. vol. vii. pi. 1, f. 12}, is more singular. 

 {Pediculus Cervif Panzer, belongs to the dipterous genus iMelophagus.) 



The other species (Nirmidca, Leach), such as liicinus, De Geer, Nirmus, Herm. & Leach, have the 

 mouth on the under side of the head, and composed, on the outside, of t^vo lips, and of two hooks and 

 maiiiliblcs. The tarsi ure very distinct, articulated, and terminated by two equal nails. 



AVith the exception of a single species, that of the Dog, all the rest are found exclusively upon birds. 

 The head is generally large, sometimes triangular, or in tlie others in the form of a semicircle or crescent, 

 and has often angular projections. It differs sometimes in both sexes, as well as the antenna;. I have 

 perceived, in many species, two simple eyes close together, on each side of the head. 

 According to observations communicated to me by i\I. Savigny, these insects have 

 maxilla;, with a very small palpus upon each, hidden by the lower lip, which has also 

 similar organs. They have, also, a kind of tongue. 



M. Leclere de Laval has stated to me that he discovered, in their stomach, morsels 

 of the feathers of birds, which he believes is their only food. De Geer asserts, never- 

 theless, that he found the stomach of the Ricinus of the Chaffinch filled with blood, 

 with which it had gorged itself. It is also known that these insects can suljsist but a 

 PivNNis. ^.g^.j, jfjp^j jim(. iijjon dead birds. They are then ohserved crawling, with uneasiness, 



upon the feathers, particularly upon those of the head, and near the beak. Redi has figured a great 

 number of species, [as has also Lyonnet, in his posthumous memoirs]. 



Some species have the month situated near the anterior extremity of the head ; the antenncc are inserted at the 

 side, at a distance from the eyes, and are very small. PedicnUs Sterna^, llinindhds, Linn., &c. 



In the other species, the mouth is nearly central ; the antennae placed very near the eyes, and their length is 

 nearly equal to that of half the head. Ricinus Gallinte, De Geer, &c. 



A celebrated German naturalist. Dr. Nitzsch, deeply studied the internal and external anatomy of these animals, 

 of which he published a memoir in Gcrmar^s Magazine. The triie genus Pediculus, or the species provided with a 

 suctorial mouth, is arranged by him with the Epizoical Hemiptera. The genus Ricinus, De Geer {Nirmus, Herm.), 

 or the species provided with mandibles and maxilla;, are referred to the order Orthoptera, and collectively named 

 Mallop/taga. Two genera of the latter are allied to the former, in being found upon various Mammalia. They are 

 Trichodccles, having the maxillary palpi obsolete, aud living upon the Dog, Badger, &c. ■, and Gtjropus, having 

 distinct maxillary palpi, and living upon the Guinea-pig. The last-named genus has the mandibles entire, and the 

 labial palpi obsolete, thus differing from Liotheum, which has the mandibles_bidentate, the labial palpi distinct, 

 and the tarsi terminated by two nails. The species are found on various birds, as are also those of the last genus, 

 Philopterus, which have 5-jointed antennie, the third often branched in the males, and the maxillary palpi are in- 

 distinct. We have not space to enumerate the subgenera into which Nitzsch has divided these genera, in all of 

 which the pro- and mesothorax compose the trunk, the metathorax being soldered to the abdomen. The subgenus 

 Goniodcs is restricted to the gallinaceous birds. We have described a species of Philopterus in detail, in the col- 

 lection of memoirs at the end of our Hislori/ of Ants. 



M. L. Dufour has formed a new genus {Triongulittus) for the Pediculus Melitta: of Kirby, previously observed by 

 De Geer, wdio regarded it as the lan'a of Meloe proscarabmis. If it be not the larva of this insect, as Kirby sup- 

 posed, doubtless it would form a distinct subgenus in the order Parasita ; but Messrs. Serville and Saint I'argeau 

 have confirmed De Geer's statement, [as it has also been by numerous recent English observers, as Doubleday, 

 Newport, Newman, Jenyns, &c.] 



[In addition to the species figured by Redi, De Geer, and Lyonnet, and those indicated (from the species of ani- 

 mals attacked), but not specifically described, by Nitzsch, various species have been described by L. Dufour in the 

 Annates de ta Societe Entomotogique de France; and by J. G. Children, Esq., in the Appendix to Captain Back's 

 Yoi/age to the North Pole. Mr. Denny has also announced an illustrated monograph of the order.] 



THE FOURTH ORDER OF INSECTS,— 



SUCTORIA, De Geer, (Siphonaptera, Latr., [Aptera, M'Leay ; Aphaniptera, Kirby]),— 



Terminates the Apterous Insects, and lias the mouth formed of a sucker of three* pieces, in- 

 closed between the articulated plates, forming together a rostrum or beak, either cylindrical 



• n<rsc-l niilv rtprescTUs t,vo, but I-Jirbv itiid Strnuss tiavc ob.scTvcd one more. According to tlic latter, tlie Bualcs covering tlie l,fise of the 

 bciik JVC tlie i' .lin. 



