206 Annals Entomological Society of America  [Vol. XIV, 
A point of great value in the use of these structures is their 
usefulness in the case of mutilated specimens. Alcoholic, rubbed, 
or broken specimens are often wholly unintelligible from the 
standpoint of the characters generally employed. The genitalia, 
however (protected within the hard, enveloping sclerites of the 
abdomen), are apt to be the last parts to be injured. Interesting 
and valuable applications of this knowledge will at once occur 
to every one; as in the examination of the contents of avian 
or amphibian stomachs, or the elucidation of valuable, but 
poorly-preserved, type specimens or others of historic value. 
BIBLIOGRAPHY. 
(1). Berlese, A., Gli Insetti. Societa Editrice Libraria, Milano, 1909. 
(2). Herve-Bazin, J., Syrphidz recueillie au Congo Belge par le Dr. J. Bequaert 
I, II, I1I, IV. Revue Zoologique Africaino, Vol. III, Fasc. 2 and 
3, 1913-14. 
(3). Howard, Dyar and Knab, The Mosquitoes of North America. 
(4). Johannsen, O. A., The Mycetophilidae of North America, I, II, III, IV, 
Bull. Maine Agr. Exper. Sta. Nos. 172, 180, 196 and 200, Dec. 1909 to 
Dec. 1911. 
(5). Lundbeck, William, Diptera Danica, Part V, Copenhagen, 1916. 
(6). Peytoureau, S. A., A Contribution a l’etude de la Morphologie de 1’Armure 
genitale les Insectes. Bordeaux, 1895. This paper gives an excellent 
bibliography of the subject down to that date. 
(7). Snodgrass, R. E., The Hypopygium of the Dolichopodidae. Proc. Cal. Acad. 
Sci., ser. 3, Vol. III, Zool. No. 11, 1904. : 
(8). Verrall, G. H., British Flies, VIII, London, 1901. 
(9). Wesche, Walter, The Genitalia of both the- Sexes in the Diptera, Trans. 
Linn. Soc. London, Ser. II, Zool. Vol. IX, 1906. 
(10). Williston, S. W., Synopsis of the North American Syrphidae. Bull. U. S. 
Nat. Mus. No. 31, 1886. 
(11). Newell, Anna Grace, The Comparative Morphology of the Genitalia of 
Insects. In Annals Ent. Soc. Amer. XI, 2, June, 1918. 
