178 
BRITISH GALLS 
Homop- 
tera 
M 
Acari 
Fungi 
Aphis shining, dark green or black, globular. (Text, 
Fig. 21 b.) 
Tetraneura ulmi I)e Geer 304 
Connold, Veg. Galls, pi. 108; Plant Galls, fig. 107. 
Houard, No. 2048. 
Leaf margins folded upwards, midrib much swollen, 
yellowish-green, aperture on the upper surface. Lateral 
veins slightly swollen. June to October. 
Tetraneura alba Ratzeburg 305 
Connold, Veg. Galls, pi. 108; Plant Galls, fig. 106. 
Leaf margin swollen and rolled inwards. See No. 302 
and Text, Fig. 21 a. 
SCHIZONEURA ULMI Linn. 306 
Buckton, ii., 100. Houard, No. 2050. 
Leaf completely deformed and hypertrophied, dilated 
and contorted to form a densely hairy bladder, 60 to 80 
mm. in diameter. Green at first, slowly becoming brown, 
and remaining attached to the branch after the normal 
hairs have fallen. Aphis black, clothed with cottony 
filaments. 
SCHIZONEURA LANUGINOSA Hartig 307 
Connold, Plant Galls, fig. 105. Buckton, iii., 104. 
Houard, No. 2051. 
Midrib of leaf swollen. See No. 301. 
Pemphigus pallidus Halliday 308 
Buckton, iii., 127. 
Minute pustule, about 1 mm. in diameter, on the upper 
surface of the leaf, opening on the lower surface in a 
minute cylindrical protuberance. Green and red ; often 
very numerous. 
Eriophyes ulmi Nalepa 309 
Houard, No. 2053. 
Dense mass of twigs on a branch, forming a “witch’s 
broom.” The leaves on the abnormal twigs are atrophied. 
Exoascus TURGIDUS Sad. 310 
Swanton, Haslemere Mus. Gaz., i., 531. Connold, 
Plant Galls, p. 95. 
Leaves blistered. See No. 303. 
Taphrina ulmi Johans. 311 
Massee. Textbook of Plant Diseases, p. 92. 
