'§.337. THE INSECTA. 421 



the Hemiptera, the suctorial apparatus is lengthened into a Rostrum, by 

 the under lip being changed into two quadri-articulate grooves united so 

 as to form a tube, and enclosing the setiform mandibles and maxillae/^ 

 With the Lepidoptera, the changes are still greater, for the mandibles are 

 only very small appendages, while the maxillae are transformed, each, into a 

 semi-canal which can be rolled up spirally, and when united form an organ 

 of suction [Lingua spiralis). At the base of this last are two very short 

 maxillary palpi, bi- or tri-articulate, while the two tri-articulate and very 

 hairy labial palpi consist of two pretty large appendages between which the 

 suctorial tube retreats when rolled up/^^ 



The buccal organs begin to atrophy with the Aptera. The four palpi 

 present with the Lepismidae, are already wanting with the Poduridae ;^'°' 

 and with the Nirmidae, they, as well as the maxillae, are very small, while 

 the mandibles are quite large. 



With the Pediculidae, there are still wider modifications ; for here there 

 is a protractile suctorial tube composed of four stiff bristles (rudimentary 

 jaws) which are enclosed in a soft and equally protractile sheath (under 

 lip.)'"' 



With the Larvae of Insecta, the buccal organs are most usually masti- 

 catory ; for, not only the larvae of the Coleoptera, the Orthoptera, and many 

 of the Neuroptera and Hymenoptera, have the same organs of this kind (mas- 

 ticatory) as the perfect insects,*^-' but also the larvae of the suctorial Lepidop- 

 tera,*^''' and those with a distinct head of certain Diptera <^*' with which, how- 

 ever, the maxillae and palpi are very frequently wanting. <^^^ But with the 

 acephalous larvae of Diptera, those of the Strepsiptera, as also with the 

 parasitic ones of some Hymenoptera, the mouth is formed rather for suck- 

 ing than for masticating the food ; for, on the inner side of the soft tumid 

 lips, either the horny organs are wholly wanting, *^^> or the mouth is armed 

 with two parallel hooks, which are used partly to grapple and partly to 

 puncture the bodies these animals attack. *^^' 



bres, I. PI. IV. fig. 1, and Newport, Cyclopaed. W Such are the larvae of Culex, Chironomus, 

 loc. cit. fig. 379-381.* Coret/ira and Simulia, and many other of the 



8 Savigny. Jlem. &c. I. PI. IV. fig. 2, 3 ; aquatic Tijjulariae. 



Ratzeburg, .Mediz. Zool. II. Taf. XXVII. ; and 15 In the larvae of Sciara, Mycetophila, ^cio- 



Burmeisttr, Handb. &c. II. Taf. I. phila, Ceroplatus, &c., which live in rotten wood 



9 This suctorial tube is pretty long with the Papi- or in fungi ; see L. Dufour, Ann. d. Sc. Nat. XI. 

 lionidae and the Sphiugidae ; it is very short with 1839, p. 201, PI. V. fig. 23, XU. p. 10. 



many Bombycidae and Pyralidae ; see Savigny, 16 The mouth of the apodal larvae of the Strep- 



M6m. &c. I. p. 1, Ph I.-UI. ; Ratzeburg-, Die siptera (see my researches in fFiegman7i's Arch. 



Forstinsekt. II. p. 2, Taf. I. ; and Newport, 1843, I. p. 169, Taf. VII. fig. U), and of the young 



Cyclopaed. loo. cit. p. 900, fig. 377, 378. larvae of Microgaster (Ratzeburg, Die Iclineu- 



10 Nicolet, Recherch. p. 34, PI. IV. mon. d. Forstinsekt. p. 13, Taf. IX.) has, in place 



11 Burmeisier, Linnaeaentomologica. II. p. 569, of jaws, soft papillae which, as these larvae ap- 

 Tab. I. proach the end of their development, are changed 



12 See Ratzeburg, Die Forstinsekt. I. III. ; into horny jaws by means of which these Insecta 

 Hartig, Die Aderfluger Deutschlands, Taf. I.- make a passage into the skin of the animals in 

 VIII.; Burmeister, Trans. Entom. Soc. I. PI. which they live. 



XXni. XXIV. (Calosoma), and Naturgesch. d. 17 With the Muscidae, Oestridae, Syrphidae, and 



Calandra, fig. 10-12 -, tVaterhouse, Trans, entom. other Diptera ; see Swammerdaniin, Bib. der 



Soc. I. PI. m.-V. (Rhapkidia, a.ni various Coleoj)- Nat. Taf. XLIII. fig. 5, and L. Dufour, Ann. d. 



tera). Sc. Nat. I. 1844, p. 372, PI. XVI. fig. 8, 10, XII. 



13 Lyonet, Traits, &c., Pi. n. ; ajxA Ratzeburg, 1839, p. 4, PI. U. 111. 

 Die Forstinsekt. II. Taf. I. 



* [ § 337, note 7.] See in this connection the me- the mouth of the Diptera presents appendages 



men- of Blanchard (De la Composition de la bouche wholly comparable to those of the other Insecta, 



dans les Insectes de I'ordre des Dipteres, in the except that these appendages are modified in a 



Compt. rend. 1850, XXXI. p. 424), who shows that special manner. — Ed. 



36 



