no 



PSYCHE. 



[November — December 1S83. 



precious systematic part of tlie Entomo- 

 logical department. When will our 

 National museum fully warrant its name 

 by becoming the one legitimate and 

 most satisfactory repository of all such 

 collections in whatever branch of sci- 

 ence ? 



In closing this brief notice of one 

 W'hose personal relations and whose ap- 

 preciative and instructive correspon- 

 dence with the writer during the past 

 fifteen vears will ever remain a green 

 and pleasant meniorv. we \vould empha- 

 size the fact that his writings throughout 

 breathe a calm and judicial spirit, void 



of personalitv. The only instance that 

 occurs to us where he gave expression 

 to ruffled feeling is in the "Synopsis of 

 the coleopterous insects of the group 

 cicridac which inhabit the United 

 States" (Annals lyceum nat. hist. X.Y., 

 April 1849, V. 5, p 9-35). \\'i the 

 prelude to this paper he indulges in 

 some severe reflections on the exclusive 

 attitude of the Latin or South European 

 countries toward the scientists of otiier 

 countries, more particularlv as exem- 

 plilicii 1)\ Spinola's work — reflections 

 not altogether unwarranted even at the 

 present time. 



GILLS OF INSECT-LARVAE. 



BY GEORGE M.\CLOSKIE. PRINCETON, N. J. 



The gills of aquatic larvae of insects These structures have been described 



consist of elastic sacs arising as out- by Reaumur. Leon Dufoiir. Audouin, 

 growths of the epidermis and enclosing Oustalet,^ and man\- others. Our pres- 

 a system of fine branches from the air- ent purpose is to rectify an error in 

 tubes or tracheae, being thus pneumatic their anatom\-, as usually represented, 

 branchiae. They vary greatly in the which has inipintant bearings on other 



questions. 



It is usual to describe the laminae of 

 the pneumatic gills as containing sys- 

 tems of fine tracheal loops, somewhat 

 after the (pattern of a plurality of carbon- 

 wicks in an Edison lamp. Oustaiet 

 says, for example, in tiie Annates des 

 sciences natiirellcs (1869. s. 5. v. 11), 

 that the branchial laminae ••inehule a 

 verital)le chevelu of traclieae folded on 

 tlieniselves so as never to reach the 

 extremity of the fingers of the glove ;" 

 and that they serve as a loose shcatli 



number of the sacs, in the number and 

 complexity of the enclosed air-tubes, 

 and in their position. In the chnidae 

 (of coleoptera) they are simple and 

 are distributed ventrally on the abdo- 

 men ; in KpJicnicra (of neuroptera) tiiev 

 are also simple, and extend from the 

 sides of the al^domen ; .sometimes they 

 are caudal appendages, and in the 

 libellulldae, or dragon-flies, they be- 

 come complex, having in some cases 

 many sac-like lamellae, and many hun- 

 dreds of branches in each, the whole 

 structure - planted within the rectum, 

 from the walls of which the lamellar 

 sacs open like so many pockets. 



1 .\nn. dcs sci. n:it., Zool., 1S52, s. 3, v. 17; 1S62. s. 4, 

 V. 17; 1S69. s. 5, V. II ; 1872, s. 5, V, 16. 



