202 NEW YORK STATE MUSEUM 



talia; dorsal plate short, deeply and triangularly incised, the lobes 

 diverging, obliquely truncate; ventral plate long, broad, tapering, 

 broadly and roundly emarginate, the lobes short, broadly rounded; 

 style long, stout, narrowly rounded. Type Cecid. 1389. 



Itonida excavationis Felt 



1907 Felt, E. P. N. Y. State Mus. Bui. no, p. 139 (C. excavata); separate, 

 p. 42-43 (Cecidomyia) 



1908 N. Y. State Mus. Bui. 124, p. 415 (Cecidomyia) 



The pale yellowish male was taken May 21, 1906 on soft maple, 

 Acer rubrum, at Albany, N. Y. 



Male. Length .75 mm. Antennae longer than the body, rather 

 thickly clothed with short, dark brown setae, pale straw color; 

 fourteen segments, the fifth with stems two and two and one-half 

 times their diameters respectively. Palpi; the first segment short, 

 subquadrate, slightly swollen at the distal third, the second twice 

 the length of the first, slender, the third a little longer, more slender, 

 the fourth one-half longer than the third; face yellowish white. 

 Mesonotum reddish browTi Avith distinct submedian yellowish lines 

 sparsely clothed with setae. Scutelltmi yellow, tipped with carmine, 

 postscutellimi yellow. Abdomen pale reddish yellow with slightly 

 fuscous areas dorsally on the second and third segments. Wings 

 hyaline, costa pale brown; halteres yellowish transparent. Legs 

 variably brown tinged with reddish, lighter ventrally, the anterior 

 and mid tarsi distinctly darker than the posterior; claws slender, 

 slightly curved. Genitalia (pi. 19, fig. 4); dorsal plate broad, deeply 

 and roundly emarginate, the lobes widely separated, narrowly 

 rounded; ventral plate narrow, narrowly rounded; style long, tap- 

 ering, the margins slightly convolute, broadly rounded. T3rpe 

 Cecid. 65. 



Itonida opuntiae Felt 



1910 Felt, E. P. Ent. News, 21:10-12 (Cecidomyia) 



1915 N. Y. State Mus. Bui. 175, p. 39-41 



1918 N. Y. State Mus. Bui. 200, p. 172, 173 



Midges were reared during June, July and August 1909, from 

 discolored areas accompanied by more or less decay (fig. 37), at the 

 base of spines on Opuntia leaves received from George V. Nash, 

 head gardener of the New York Botanical Gardens at Bronx Park, 

 N. Y. Apparently the eggs are deposited at the base of a spine, 

 possibly near some recent wound and the larvae commence opera- 

 tions upon the tissues, their work being followed by decay and in 

 some instances by the operations of a small Ptinid beetle belonging 

 to the genus Catorama. In the latter case the dead tissues are 

 traversed by irregular galleries, the Cecidomyiid larvae being in the 

 near vicinity of living cells. This species occurred in New York 

 in the leaves of Opuntia banburyana from Italy and an 



