INSECTS. 



fion for eating, and polTefs only an imperfeft moutli, without 

 any manJible, and with membranous maxillae attached to the 

 vliolc length of the lower lip. 



The family of the odonata, or libcUulae, wiiich are the 

 moll (Irongly armed, and the moft cruel of infeCls, is of a 

 nature quite oppofite to thefe. Their mandibles have an 

 anterior, hooked, and. as it were, cutting portion, and a pof- 

 terior truly molar furface, with four pointed tubercles. It 

 is curious to obferve in thefe infeclivorous infefts the fan*e 

 characters as in the quadrupeds which are nouriflicd by 

 fimilar food. The masillas are divided into long pointed 

 dcnticulations like needles, and have palpi witliout articula- 

 tions. An enormous lower lip covers all tiiis apparatus ; it 

 is divided into three or four lobes, of which the lateral ones 

 are themfelves fometimes terminated in the form of pincers. 



The other nemoptera are lefs diftinctly characterized. 

 They have, in general, llronger or weaker mandibles ; 

 maxillx with artictilated palpi, which are two in number for 

 each maxilla in the myrineleon and the afca'aphus, and foli- 

 tary in the others ; a lower lip, terminated by a tongue, 

 which is fimple in molt kinds, divided into four in the termes 

 and pfociis, having two very large and club-lhaped articu- 

 lated palpi in the myrmeleon ; and no particular characters in 

 the other genera. 



The moil curious mouth, in this order of infeft?, is th.it 

 cf the panorpa. Its mandibles are fmall, and placed at tiie 

 end of a long fnout •, of which the under part is lilled by a 

 lip, and very elongated maxiilx confolidated together. Here 

 the fubdivilion of the lip commences, into the horny piece 

 (g.uiache of Latreiile) at the bafis, which fupports the la- 

 bial palpi, and the tongue, or membranous organ, placed at 

 the extremity between the labial palpi. 



3dly. In the Hyminoptera. — This natural family, the mull 

 intereiling of the infetl tribe, by the numerous and varied 

 inilinfta with which the different fpccies are endowed, has, 

 in the ftruclure of its mouth, a ciiaraCter of which the firft 

 appearance has jull been indicated in the panorpa. Part of 

 the bafis of the maxilla, and the horny portion of the lower 

 lip (the ganache), are there united by a membrane, and are 

 always moved together. The portion of tlie jaw beyond the 

 feeler covers the tongue more or lefs, and ferves it for a 

 ftieath, which is fometimes very complete. 



The hymenoptera, which fuck the neClar of flowers, may 

 be recognized by the prolongation of their maxills and 

 loiver lip, which are often much .longer than the head, but 

 admit of being folded up fo as to be withdrawn under 

 the production of the mandibles. This kind of organ is 

 fometimes placed on a pedicle, which admits of being moved 

 backwards and forwards. This may be feen in the bee and 

 the neiiilibouring genera. In thefe elongated trunks the 

 tongue forms the cfi'ential part, the true fucking tube : but 

 it is always only rolled fo as to form a half tube, and opens 

 longitudinally below. ' 



In the bee, one of the articulations of the labial palpi 

 i.'i prolonged, and forms the firll fheath of the tongue ; the 

 outer portion of the jaw is prolonged in a fimilar way to 

 form a fecond (heath ; Fabricius calls this ilrntture lingua 

 quinquefida. In the Eucera (Fabr. ) two fcales of the 

 bafis of the tongue, which are clearly feen in the bee, 

 where they are very fmall, are prolonged as much as 

 the tongue, and the organ is therefore a lingua feptemllda. 

 In other genera the labial palpi do not ferve for Iheaths, 

 and the trunk is therefore trilid, as in the fphex arenaria, 

 &c. Even where the tongue is not prolonged into a trunk, 

 it is always opened below ; and this is a character peculiar 

 to the hymenoptera, whence it refults that their mandibles 

 6 



afilfl; them but little in procuring their food, but ferve 

 them merely as armour, and as inilruments for working. 

 Wluit they might chew would arrive with difficulty at the 

 under furface of the tongue to be fwallowed ; but the lat- 

 ter organ imbibes nutritious matter in the liquid fofm, or in 

 a ilate of minute divifion, as the pollen of plants, &c. 

 Thefe genera with (hort tongues prefent verv interefting 

 differences in the form of the organ. It is fometimes fimple 

 and conical, as in the evania, or formed like an oval fpoon, 

 as in the firex, the mutilla, and the hornet, or dilated and 

 grooved, as in the leucopfis, or divided into three pieces, as 

 in the tenthredo, or into three conical and villous bridles, 

 as in the feolia, or more or lefs equally and deeply divided 

 into three or four lobes, as in the vefpre, and moit of the 

 genera feparated from that of fphex, ^^c. Thefe different 

 configurations determine the kind of food which the animal 

 employs, and the fituations in which it procures it. The 

 differences of the maxil'a are lefs important : it forms in 

 front merely a fcaly piece, covering the tongue above, and 

 havitig its length proportioned to that of the tongue. 



The palpi vary more in their abfolute and relative length, 

 in the form and number of their articulations. The bee 

 has exceedingly fmall maxillary palpi. The fame may be 

 faid of the firex, but the labial palpi are here large and 

 club-fhaped. Moft others have them filiform or fetaceous, 

 and with feveral joints. The upper lips fometimes affumes 

 a peculiar form for a particular office. In the leaf-cutting 

 bees, for example, it forms a fcaly fliield, protecting the 

 trunk, upon which it is folded back, that it may not be in- 

 jured by the edge of the leaf which tlie mandibles cut. 



4thly. /n /A.- Co/ra/^r^. — Thefe, although they arc ex- 

 cefiively numerous, form a natural order. Their lower lip 

 is not placed between the maxills, as in the preceding or- 

 der, but really below, fo as to conceal a part of them, 

 when the mouth is obferved from below ; confequently they 

 are articulated between the lip and the mandibles, and not 

 fufpended with the lip in a common membrane, as is the 

 cafe in the hymenoptera. The opening of the pharynx is 

 alio formed upon the tongue, and not below it, as in the 

 hymenoptera, fo that the produce of malHcation takes that 

 direction naturally. Such are the true characters of tlie 

 mouth in this order ; but that of having the maxilla free 

 froiat adhelion to the hp is not exclufive, as Fabricius feems 

 to have fuppofed, when he founded on this idea the name 

 of eleutherata, which he has given to thefe infects. 



There feems to be only one family in this order, of which 

 the character is determined in a linking manner by the 

 organization of its mouth ; it is that of the carnivora. All 

 of thefe have prominent mandibles and maxilla, which are 

 alfo hooked and cutting, four maxillary and two labial- 

 palpi ; confequently they are terrible enemies to other in. 

 lefts. The chief circumftance, by which they are diilin- 

 guilhed from each other, is the figure of the horny and 

 membranous part of the tongue, which are more or lefs lo- 

 bated : they may alfo differ is fome unimportant acceffory, 

 as the fpines of the maxillx, &c. 



Another family, as natural as the preceding in all the cir- 

 cumftanees of its external and internal organization, that of 

 the lainellicornia, poffeiTes fcarcely any common charafters 

 in the parts of the mouth. Some have enormous projeftiug 

 mandibles, more or lefs refembling the horns of the (lag 

 (incanus) ; others have only (hort but ftrong mandibles 

 (the dung-beetles, geotrupcs of I.atreille) ; in others they 

 are membranous and fcarcely vifible (the cetonix, Fabr.the 

 fcanlbxi, the copris.J 



Some haye ttrong maxillx well fnrniflicd with teeth (the 

 melolontbx, 



