No. 34.] HEMIPTERA OF CONNECTICUT: MEMBRACIDAE. 1 99 



Key to Species. 



1. Crest distinctly highest at anterior extremity 2 



Crest highest just behind anterior extremity helena 



2. Species small, 5-6 mm t 3 



Species large, 7-9 mm '. castaneae 



3. Pronotum punctate; female green, male black with broken yellow 



dorsal stripe querci 



Pronotum smooth ; both sexes green inornata 



A. castaneae (Fitch). (PL iv, 23.) 



1851. Smilia castaneae Fitch. Cat. Ins. N. Y., 49. 



1851. Thelia castaneae Walker. List Horn. Brit. Mus., 1143. 



1854. Gar gar a nigricephala Emmons. N. Y. Agr. Rept, v. 157, pi. 13, 

 fig. 5- 



1854. Gargara viridis Emmons. N. Y. Agr. Rept., v. 154, pi. 3, fig. 13. 



1867. Atymna castaneae Stal. Ofv. Kongl. Vet-Akad. Forh., xxiv. 554. 



1890. Ophigenna nigrocephala Smith. Ins. New Jer., 442. 



1894. Ophiderma nigricephala Goding. Cat. Memb. N. A., 440. 



1903. Atymna lineata Buckton. Mon. Memb., 194. PI. 42, fig. 6. 



1908. Cyrtolobus {Atymna) castaneae Van Duzee. Stud. N. A. Memb., 

 93- 



Abundant. A characteristic species on chestnut and found 

 wherever this tree is common. 



The forms vary remarkably in size and coloration. This 

 peculiar variation does not seem to be sexual or seasonal and its 

 cause is not known. Three forms are quite distinct — one large, 

 immaculate green, another large, very dark brown, and a third 

 small, light castaneous with very dark brown tegmina. Some 

 differences have been noted between the nymphs that develop into 

 these different forms, but not enough to warrant a taxonomic 

 distinction. The variety that seems to be the most constant and 

 most abundant is castaneous with a dark brown patch over each 

 humeral angle and a brown line on the dorsal margin. The crest 

 is highest at the front, gradually sloping to the apex of the posterior 

 process which is short, not reaching the tips of the tegmina. The 

 tegmina are deep castaneous with brown bases and tips. 



It is not known whether or not the entire life history is passed 

 on the chestnut as the complete series of instars has never been 

 reported. The nymphs appear on this host in large numbers, 

 however, about the middle of June and the adults about a month 

 later. Both feed on petioles and blades of leaves. This species 

 is one of the best fliers of all of our membracids and is commonly 

 taken about lights. It is often taken on oaks in the vicinity of 

 chestnuts and may spend part of its life on this host. 



Hosts : Chestnut, red oak, white oak. 



New Haven, 20 July, 1904; 21 June, 1909; 1 July, 1913 (B. H. W.) ; 

 13 July, 1904 (W. E. B., P. L. B.) ; 18 June}, 1902 (E. J. S. M. ) ; West 

 Haven, 27 June, 1905 (H. L. V.) ; Westville, 18 June, 1904 (W. E. B.) ; 

 Litchfield, June to Aug. (L. B. W.). 

 A. querci (Fitch). 



185 1. Smilia querci Fitch. Cat. Ins. N. Y., 49. 



1851. Thelia querci Walker. List Horn. Brit. Mus., 1143. 



