478 TEXT-BOOK OF ENTOMOLOGY 



day under water, in a stream or rivulet, fixed firmly to a stone in the rapid part 

 of the stream," with its head turned up stream ; but leaving the water at dark. 

 The under side of the body, including the head, is hollowed so that the creature 

 may adhere, sucker-like, to smooth stones ; the claws, claspers, and flaps on the 

 legs aid in retaining its hold, while the outer margin of the legs is dentate and 

 thickly fringed with hair to repel the water. 



Another form, closely related to Prisopus, from Borneo (Cotylosoma dip- 

 neusticum) is said by Wood-Mason to be even more profoundly modified for an 

 aquatic life, since it has not only spiracles, but also, as he claims, tracheal gills. 

 From each side of the body, in fact along the lower margins of the sides of the 

 metathorax, there stand straight out five equal, small, but conspicuous ciliated oval 

 plates, " which, when the insect is submerged and its stigmata are closed, doubt- 

 less serve for respiration." The author did not note the actual presence of 

 tracheae in these plates. 



LITERATURE ON THE ORGANS AND PHYSIOLOGY OF RESPIRATION 

 a. On the tracheal system in general 



Lyonet, P. Traite" anatomique de la chenille qui ronge le bois du saule. (La 



Haye, 1760; 2d edit., La Haye, 1762, pp. 616, 18 Pis.) 

 Treviranus, G. R. Beitrage zur Anatomie und Physiologic der Tiere und 



Pflanzen, 1816. 



Das organische Leben. Bremen, 1831. 

 Rengger, J. R. Physiologische Untersuchungen iiber die tierische Haushaltung 



der Insekten. Tubingen, 1817. (Germar's Mag. f. Ent., 1818, iii, pp. 410- 



413.) 

 Dufour, L. Eecherches anatomiques sur les Carabiques et sur plusieurs autres 



insectes Cole'opteres. Organes de la respiration. (Ann. Sc. nat., viii, 1826, 



pp. 19-27, 2 Pis.) 

 Etudes anatomiques et physiologiques sur les insectes Dipteres de la 



famille des Pupipares. Appareil respiratoire. (Ann. Sc. nat. Zool., Se"r. 3, 



iii, 1845, pp. 56-64, 1 PL) 



Description et anatomic d'une larve a branohies externes d'Hydropsche. 



(Ann. Sc. nat. Zool., Se> 3, 1847, viii, pp. 341-354.) 

 Etudes anatomiques et physiologiques, et observations sur les larves des 



Libellules. Appareil respiratoire. (Ann. Sc. nat. Zool., Se"r. 3, xvii, 1852, 



pp. 76-97, 3 Pis.) 



Recherches anatomiques sur les Hyme"nopteres de la famille des Uro- 



cerates. Appareil respiratoire. (Ann. Sc. nat. Zool., Se"r. 4, i, 1854, 



pp. 203-209, 1 PI. ; see also p. 344.) 



Burmeister, H. Handbuch der Entomologie, i, 1832, pp. 169-194, 416-436. 

 Kirby, W., and W. Spence. Introduction to entomology, 1833, iv, pp. 35-81. 

 Bowerbank, J. S. Observations on the circulation of blood and the distribution 



of the tracheae in the wing of Chrysopa perla. (Ent. Mag., iv, 1837, 



pp. 179-185.) 

 Plainer, E. A. Mitteilungen iiber die Respirationsorgane in der Haut bei der 



Seidenraupe. (Muller's Archiv f. Physiol., 1844, pp. 38-49.) 

 Filippi, F. de. Alcuni osservazioni anatomico-fisiologische sugl' Insetti in 



generate, ed in particulare sul Bombice del Gelso. (Ann. R. Acad. d' Agri- 



coltura di Torino, 1850, ii, p. 25, 1 PI. ; Transl. by C. A. Dohrn, Stettin, 



Ent. Zeit., 1852, xiii, pp. 258-267 ; xiv, pp. 124-132, 1 PI.) 



