166 Proceedings of the Biological Society of Washington. 



first brood appear during the last of June and first part of July after which 

 eggs are again laid, the adults of this second generation hibernating and ap- 

 pearing the following spring. 



Gargaphia tiliae was described in 1864 by Walsh. Van Duzee in his Cata- 

 logue of Hemiptera gives the following references to the species : 



Walsh, Proc. Ent. Soc. Phil. Ill, p. 408, 1864. 



Uhler, Checklist, p. 22, 1886. 



Provancher, Pet. Faune Ent. Can. Ill, p. 159, 1887. 



Bergroth, Revue d'Ent. XI, p. 264, 1892. 



Van Duzee. Bui. Buf. Soc. Nat. Sci. V. p. 181, 1894. 



Gillette & Baker, Hemip. Colo. p. 57, 1895. 



Bueno, Jl. N. Y. Ent. Soc. XVIII, p. 31, 1910. 



Smith, Cat. Ins. N. J. ed., 3, p. 149, 1910. 



Osborn & Drake, Ohio St. Univ. Bui. XX, p. 234, 1916. 

 syn. fasciata Stal. Enum. Hemip. III. p. 125, 1873. 

 Wirtner, Ann. Cam. Mus. Ill, p. 202, 1904. 

 Smith, Cat. Ins. N. J. ed. 3, p. 149, 1910. 



Localities, N. Y., N. J., Pa., Va., Ohio, 111., Kan., Colo. 



To the above references to the species can be added the following : 

 Drake, Ent. News, XXVIII, p. 227, 1917. 



Parshley, Fauna New Eng. Hem. Heter., Bost. Soc. Nat. His. 

 VII, 14, p. 56, 1917. 



This latter reference adds New Hampshire, Massachusetts and Connec- 

 ticut to the list of localities. 



Egg. Length 0.48 mm. Width 0.18 mm. Suboval, one side more con- 

 vex than other; basal part acute with rounded end, slightly constricted 

 where inserted in leaf tissue; widest across basal half; extremity of apical 

 end truncate with rim-like collar and central cone-shaped nipple projecting 

 only slightly or not at all; translucent except for apical third which is cov- 

 ered with a light brown varnish-like material. 



First Stage Nymph. Length 0.45 mm. Elliptical; whitish except artic- 

 ulations of antennal segments, dorsal surfaces of thorax and abdomen, and 

 outer surfaces of legs which are light brown (some specimens are almost en- 

 tirely white); antennae two-thirds length of body bearing stiff hairs; eyes 

 lateral, consisting of five, distinct, red ommatidia; head, thorax and abdo- 

 men bearing minute, dorsal tubercles each tipped with a hair; legs long; 

 rostrum brownish at tip, extending beyond bases of third pair of legs. 



Second Stage Nymph. Length 0.75 mm. Similar to preceding stage in 

 color, shape and markings; some specimens are entirely light brown; an- 

 tennae almost three-fourths length of body; tubercles becoming spine-like 

 and similar in arrangement to those of third stage nymph. 



Third Stage Nymph. Length 1.25 mm. Antennae two-thirds to three- 

 fourths length of body; body oval; antennae, dorsal surfaces of head and 

 thorax, and median, dorsal portion of abdomen tinged with brown, remain- 

 der white (some specimens whitish except for last antennal segment and 

 spines on head, thorax and median, dorsal portion of abdomen which are 

 brown; articulation of femur and tibia and tip of tarsus brownish; spines on 



