^ 337. THE INSECTA. 421 



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

 the under lip being changed into two qaadri-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 Nirraidae, 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. 1-4 Such are the larvae of Culex, Ckironomua, 

 loc. cit. fig. 379-381.* Cor et lira and Siniulia, and many other of the 



8 Savii^ny, Mem. &c. I. PI. IV. fig. 2, 3 ; aquatic Tipulariae. 



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



Burmeister, Haiidb. &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 £,. Dufour, Ann. d. Sc. Nat. XI. 

 Uonidae and the Sphingidae ; it is very short with 1839, p. 204, PI. V. fig. 23, XII. p. 10. 



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



M^m. &c. I. p. 1, PI. I.-III. ; Ratzeburg, Die siptera (see my researches in IViegmann''s Arch. 



Forstinsekt. II. p. 2, Taf. I.; and Newport, 1843, I. p. 159, Taf. VII. fig. 14), and of the young 



Cyclopaed. Inc. cit. p. 900, fig. 377, 378. larvae of Microgaster {Ratzeburg, Die IcUneu- 



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

 U i3urmej«ier, LLunaeaentomologica. II. p. 569, of jaws, soft papillae which, as these larvae ap- 



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



li! 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. 



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



Calandra, fig. 10-12 ; IVaterhouse, Trans, entom. other Diptera ; see Swammerdarrim, Bib. der 



Soc. I. PI. lll.-\'. {R/iaphidia, a.nii various Coleop- 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. ; And. Ratzeburg, 1839, p. 4, PI. II. 111. 



Die Forstmsekt. II. Taf. I. 



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



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



dans les Insectes de I'ordi-e des Dipteres, m the except that these appendages are modified in a 



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



36 



