KEY TO AMERICAN INSECT GALLS 



79 



b Gall a swelling of the midvein or sometimes of the petiole (See also (13) p. 106, and (15) a, b, 



p. no) 



( i) Swellings abrupt 



Globose or spindle-shaped, woody, green petiole or midrib gall on Q. alba, 

 Q. prinus, Q. macrocarpa, Q. bicolor, Q. prinoides, 

 Q. obtusiloba. Fig. 72. Bass. '63, p. 324 



Cynipid. Oak leaf stalk gall, Andricus petiolicola Bass. 

 Polythalamous, midvein gall projecting on both surfaces, rounded beneath, 

 conical above, length 19 to 22 mm, diameter 12 mm, on Q. a 1 b a . PI. i, 

 fig. I. Bass. '90, p. 80 



Cynipid. Andricus cicatriculus Bass. 



Irregular, polythalamous, reddish brown, woody thickening of the midvein or 



leaf and containing radiating larval cells, length 8 to 15 mm, diameter 5 to 6 



mm, differs from both Andricus petiolicola and C a 1 1 i r h y t i s 



t u m i f i c a . Mex. Trotter '11, p. 131 



Cynipid. ? C y n i p s sp. 



Fig. 75. Midrib tumor gall, Callirhytistumifica O. S. 

 (Original) 



Fig. 76. Midrib tumor gall, C a 1 li - 

 rhytis tumifica O. S. Sec- 

 tion showing arrangement of larval 

 cells. (Original) 



Soft, thin-shelled, red or brown vein galls frequently closely pressed together 

 and somewhat resembling figs, onQ. alba,Q. prinoides and Q. 

 p r u n u s . Fig. 66, 84, 1,2. Beutm. 'ogd, p. 244 



Cynipid. Oak fig gall, Biorhiza forticornis Walsh 



Small, rounded, polythalamous, midvein gall projecting equally on both surfaces, 

 diameter 2 to 3 mm, onQ. parvifolia. Ashm. '87, p. 138 



Cynipid. Callirhytis parvifoliae Ashm. 



Globose, polythalamous, midvein gall near the base of the leaf, prominent on 

 both surfaces, diameter 6 mm, cells radiating from a common center and not 

 separable from woody fiber about them, on Quercus species. Bassett '90, 



P- 74 



Cynipid. Callirhytis reticulata Bass. 

 Irregular, polythalamous, globose, fleshy gall occurring near the base of the leaf 

 and projecting about equally above and below, diameter 4 to 7 mm. Ashm. 

 '97, p. 116 



Cynipid. Andricus morrisoni Ashm. 



