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TEXT-BOOK OF ENTOMOLOGY 



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

 most anterior pair of spiracles are open. 



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

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



Musca, after the tirst moult, (Estridae, Asilidae, and 

 Syrphus.) 



4. Peripneustic type; with prothoracic and ab- 

 dominal spiracles, the mesothoracic pair atrophied 



FIG. 429. Branchial tuft of nymph of ^Eschna. 



or closed. (The larvae of Neuroptera, Mecoptera, 

 Trichoptera, Lepidoptera, of most Coleoptera, 1 of 

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



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

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

 supplied with trachea! 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, Klatcr. 



-Visceral tracheal Lampyris, Lycus, Triphyllus, Eucinetus, Dascillus, 

 system of the nymph of ^xclma _/ 



maculattisima : o, (esophagus; Psephenus, Ergates, Micralymna, and probably many 

 others. The metathoracic stigmata are open in Lycus 



an d Firm's 

 <*iui Pjiiiiis. 



In the Hymenoptera the two pairs on the meso- 

 and metathoracic segments are open in the Aculoata, 

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

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

 Palmen adds that most dipterous larvae are amphipneustic ; Cecidomyia, the 

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



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

 nupa, and holopneustic in the imago stage. 



, 

 K, stomach ; M, urinary tubes ; 



B, rectum; A. anus; tv, visceral 



* . ijiji 1 1 i 



tracheal trunks ; td, dorsal trunks. 



After Oustalet. 



