May, 1916] Morphology of the Zoocecidia of Celt is 269 



The author, at this point, wishes to express his deep apprecia- 

 tion of the kindness of Dr. E. P. Felt, State Entomologist ot 

 New York, the American authority on the Itonididae, for 

 many helpful suggestions pertaining to the identity of some of 

 the gall forms herewith presented. 



Riley (28) describes one gall which has not been collected 

 by the writer. To give a character of completeness to the 

 itonid list, his data on this form will be given. 



"33. On the under side of the leaf, arising from the leaf 

 ribs, occurring either singly or in smaller or larger groups. 

 Gall rosette-shaped, resembling the seed capsule of certain 

 Malvaceous plants of the genus Hibiscus, circular in outline, 

 greatly flattened on top and here furnished with a short central 

 spine or nipple (frequently broken off) ; sides sulcate, with from 

 ten to twelve more or less marked furrows, and with the cor- 

 responding interstices convex. Surface of gall not shining, 

 lighter or darker brown, speckled with small, irregular, blackish 

 pustules, and sparsely beset with moderately long whitish 

 hairs, which are easily abraded. Average height of gall, .75 mm. ; 

 diameter 2-3 mm. Cell oblong oval, enclosed by thick, woody 

 side walls, but with a thin bottom, and at the roof (i. e. toward 

 the upper side of the leaf) covered with a thin soft layer. The 

 gall is at once recognizable from its shape, but might readily 

 be mistaken for a Psyllid gall" Riley. 



This gall is probably Cecidomyia "lituus" Walsh, which 

 is given by Felt as a "yellowish, disk-shaped gall with acute 

 apical cone on leaf." Walsh's name "lituus" should not be 

 associated with any hackberry gall. In the citation below he 

 gave this name to the grape gall now called C. viticola, and 

 mentioned, merely, the presence of two "similar galls" on 

 hackberry leaves. 



Walsh, Am. Ent. 2:28. 1869. 



Riley, 5th Rept. U. S. Ent. Comm. p. 613. 1890. 



Felt, Jour. Econ. Ent. 4. 1911. 



8. Cecidomyia unguicola Beut. (PL XVII, Figs. 8, 8a). 



On leaf, under side, a, sharply pointed cone-shaped gall 

 with flaring base. 3-5 mm. high, 2-3 mm. wide. Light green 

 to yellow in color. Smooth, almost shining. Monothalamous, 

 rarely, if ever confluent. Chamber sub-cylindric, with the 

 distal half thinner walled than the proximal. The distal one- 

 third or one-fourth of the gall is delimited proximally by the 



