6 



psrciiH. 



|J:in.— Kill. 1SS3. 



popular descriptions and brief notes 

 upon the scales of coleoptera have been 

 printed, especially in handbooks for 

 microscopists, but the important con- 

 tributions to the subject are in Dujar- 

 din's Manual for the microscope.^- in 

 Deschamps' Researches on the elytra 

 of coleoptera'' and lastly in Fischer's 

 somewhat extensive dissertation''' on the 

 scales of coleoptera, published in 1S46. 

 Fischer's dissertation was based upon 

 a large collection of coleoptera of Eu- 

 rope, which he examined and consid- 

 ered by tamilies. He classified the 

 scales o( c/irciiliom'dac into four groups 

 antl made a fifth group of the kind of 

 scales found on AntJircmis. These 

 divisions will be considered later, in 

 connection with the form and stiiiclinc 

 of the scales. 



I will begin the descriptive part of 

 mv paper with an explanation of the 

 hairs of Cicindela dorsalis, for I wisli 

 to say a good deal about scale-like 

 hairs in this paper, since the scales 

 of coleoptera are simply flattened hairs 

 of a more or less complex nature. In 

 the progress of this jiaper 1 hope to 

 be able to point out ailinities, not pre- 



" Dujardin, F. Nouveau manuel complet 

 de I'observateur aii microscope. Avec atlas. 

 Paris, 1843. 



** Deschamps, 15. Rccherches microsco- 

 piques sur rorganisation des elytres dcs 

 coleopttres. (Ann. sci. nat.. 184-;. s. 3. v. 

 3. P- 3.H-.S6.^) 



*' Fischer, L. H. Microscopische I'nter- 

 siichungen iiber die Kiiferschuppcn. Disser- 

 tation . . . Freiburg, 1846, fig. Reprint (Isis. 

 1846, V. 6, p. 401-421. fig.) 



viouslv noted, between hairs and scales 

 of coleoptera. 



H.VIRS OK CICIXnKI.,\ IlOliS.M.IS. 



The white hairs which clothe the 

 sides of the thorax of C. dor.ta/is and 

 are abundant upon nearly all parts of 

 the under side of this insect, even upon 

 its legs and upon some of its mouth- 

 parts, owe their white color to the pres- 

 ence of air in their interior. 



In transverse section tliese liairs — 

 for Ihev are scarcely flat enougli to be 

 termed scales — are circular, ellijisoi- 

 dal (as in fig. i, d) or with a slight 

 tendency to be triangular. The central 



Fig. 1. Hairs of CuiitJi-la Jorstilix: a, from thorax ; 

 ^, Siiine partly deprived of air; £-, apical end of same; 

 <i, transverse section of same; i*, basal end of same; 

 ^, hair from antenna. Enlargement: «, b and ^, lOO 

 diain. ; r, d and e, 300 diam. 



portion is a canal, about one-fourtii the 

 di;uneter of the whole hair. :in(l is filled 

 with air. This canal is surrounded i)y 

 very minute cavities forming a sort of 

 pitii-like substance filled with air and 

 extending out\\;u-d to tiie outer chiti- 

 nous covering of the h;iir. The c;i\ i- 



