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TEXT-BOOK OF ENTOMOLOGY 



2. Propneustic type. The pupre of Corethra, Culex, etc., in which only the 

 most anterior pair of spiracles are open. 



3. Amphipneustic type.. Larva? with a pair of open spiracles situated at each 

 end of the body, the intermediate spiracles being closed. (Most dipterous larva?, 



Musca, after the first moult, CEstridte, Asilidae, and 

 Syrphus. ) 



4. Peripneustic type; with prothoracic and ab- 

 dominal spiracles, the mesothoracic pair atrophied 



(&s --.7- ^NVY/JV? &?; vnw n 



s&ssy&u^::-- .. -vvH 



FIG. 429. Branchial tuft of nymph of JCschna. 



or closed. (The larvae of Neuroptera, Mecoptera, 

 Trichoptera, Lepidoptera, of most Coleoptera, 1 of 

 most Diptera, and of most of the Hymenoptera. 2 ) 



I 



FIG. 430. Part of three rows of respiratory folds from outic- 

 ular living- rectum of ^Eschna. The shaded parts are abundantly 

 supplied with tracheal tubes. The leaflets appear to be con- 

 nected with a central trachea, but this is not really the case. 

 After Miall. 



1 The mesothoracic stigmata are open in Carabus, 

 Potamophilus, Elmis, Macronychus, Buprestis, Elater, 

 Lampyris, Lycus, Triphyllus, Eueinetus, Dascillus, 

 Psephenus, Ergates, Micralymna, and probably many 

 others. The metathoracic stigmata are open in Lycus 

 and Elmis. 



2 In the Hymenoptera the two pairs on the meso- 

 and metathoracic segments are open in the Aculeata, 



also in the Siricidre, among which sometimes that on the third segment is closed. In 

 Pimpla and Microgaster (fully grown larvre) only the mesothoracic stigmata are open. 



Palme"!! adds that most dipterous larvae are amphipneustic ; Cecidomyia, the 

 Mycetophilidae, Bibionidre, and Stratiomys are typically peripneustic. (p. 92.) 



Moreover, a single insect, as Sialis, may be apueustic as a larva, peripneustic as a 

 and holopneustic in the imago stage. 



FIG. 428. Visceral tracheal 

 system of the nymph of ^Exc/ina 

 ninculntinsima : o, oesophagus; 

 J, stomach ; M, urinary tulics ; 

 It, rectum ; A, anus ; (r, visceral 

 tracheal trunks ; td, dorsal trunks. 

 After Oustalet. 



