208 FIFTH EEPORT OF THE ENTOMOLOGICAL COMMISSION. 



erable numbers in the Central Park, New York, in May, 1869. (Osten 

 Sacken, Trans. Amer. Ent. Soc. iii. 53.) 



290. Corythuca arcuata (Say). {Tingis arcuata Say.) 

 Order Hemiptera ; family Tingitid^e. 



The following notice of this bug is copied from Professor Riley's MS. 

 notes : 



June 26, 187G, found in Ofallon Park, on the under side of leaves of white oak, the 

 eggs, newly hatched larvae, and others in various stages of development, as well as a 

 few mature insects. Eggs laid in patches, but not close together, being set irreg- 

 ularly; they are pointed at both ends and attached by one end, and are of a dull 

 •black color. (See also Lintner, 4th Rep. p. 108, Figs. 42, 43.) 



^91. The oak-leaf phylloxera. 



Phylloxera rileyi Llchtenstein. 



This insect forms a yellow circular spot on the uucier side of the leaf, 



l)ut showing plainly abov^e, of the white and post oak ; the species is of 



small size and unusually slender, and with long tubercles in the pupa. 



A full account has been published by Riley in Seventh Mo. Rept., pp. 



118-121. 



292. Lachnus qaercicolens Ashmead. 



This plant louse was found by Ashmead early in February in Florida, 

 feeding on the under surface of the leaves of the live oak {Quercus 

 virens) ; winged specimens, however, were not taken until April. 



Wingless female. — Length, .05 inch, ovate ; reddish, becoming brown with age. 

 Vertex of head brown; beak reaching to the middle coxse, reddish at the base, yel- 

 lowish in the middle and brown at tip ; antennne 7-jointed, reaching to the honey 

 tubes, whitish, basal joint reddish; joints annulated at tip with black; apical joint 

 short, black ; honey tubes almost obsolete, as wide as long, whitish ; style hardly 

 visible, whitish, pubescent, legs pubescent, posterior pair dark brown or black, mid- 

 dle and anterior pair reddish-yellow, feet infuscated. 



Winged individual. — Length, .05 inch. Same as apterous female, excepting that 

 the abdomen is lighter in color ; the middle femora and coxae dark brown, and wings 

 hyaline, with the stigma and veins green. (Ashmead, Can. Ent, XIII, 155.) 



293. Phyllaphis niger Ashmead. 



This in some respects anomalous Aphis was detected feeding on 

 a tender shoot of the willow oak {Quercus phellos, variety laurifolice). 

 No winged specimens were found. The broad head, slightly pubescent 

 abdomen, and other characters exclude it from the genus Lachnus. 



Wingless female. — Length .05 inch, ovate and of a shining black color; head broad, 

 nearly as long as wide, slightly arcuate in front and with two longitudinal depres- 

 sions on the vertex; beak long, reaching beyond hind coxae, black at base, but be- 

 coming reddish towards tip and slightly pubescent, antenna 7-jointed, situated very 

 widely apart and not on tubercles, brownish in color, with the terminal joint very 

 minute; metathorax a broad, smooth, shining, convex plate; abdomen wider than 

 long, and sides flattened to honey tubes, slightly pubescent ; honey tubes black, almost 

 obsolete, as wide as long ; style not visible, anus pubescent ; legs dark brown, ap- 

 proaching black, pubescent, posterior pair long. (Ashmead.) 



