WALTER] CLASPING ORGANS IN HYMENOPTERA 85 



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1893. KolbE, H. J. : Einfiihrung in die Kenntnis der Insekten. Berlin. 



1900. KoschEwnikoff, G. A. : Materialien fur die Naturgeschichte der Biene. 



Ref. v. Bachmetjeff in Allg. Z. f. Ent, vol. 8, No. 2, 3, pp. 37-44. 

 1867. Landois, H. : Die Ton-und Stimmaparate der Insekten. Leipzig. 

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Sci. Nat. Paris, vol xv, pp. 1-69. 



1886. : La machine animale Locomotion terrestre et aerienne. Paris. 



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 1895. Sharp, D. : Insects. Pt. I. In The Cambridge National History, vol. 5, 



PP. 83-565- 

 i860. StavELEy, E. F. : Observations on the Neuration of the Hind Wings of 



Hymenopterous Insects, and on the Hooks, which join the Fore and 



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 1862. : Notes on the form of the Comb (Pecten) in different Andre- 



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VIII. Explanation op Plates 



All figures are photomicrographs, prepared with a Leitz microscope and 

 a Zeiss microphotographic apparatus. Figs. 1 and 3 are taken with a Zeiss 

 microplanar; all the others, according to magnification, with the Leitz ob- 

 jectives 3, 5, 8, without eye piece, partly by Welsbach light and partly by day- 

 light. 



The following abbreviations apply to all figures : 



3 1, B 2, B 3 Marginal bristles. 



D H Costal vein ; oC A, upper ; u C A, lower branch. 



C A Distal hooks. 



F Chitinous threads. 



Gr Border layer between wing-matrix and lumen of the hook. 



Hi Hind wing. 



L Lumen of the costal vein. 



1 Longitudinal ridge of the groove of the fore wing. 



Ma Matrix of the costal vein. 



Me Drum-membrane of the "pan." 



oL Upper wing-lamella. 



P Pan. 



R Annular ridge. 



Ri Groove of the fore wing. 



SbH Subbasal hooks. 



uL Lower wing-lamella. 



Vo Fore wing. 



Z 1 Tubercles at the anterior margin of the hind wing. 



Z 2 Tubercles on the outer side of the groove. 



