CATALOGUE OF BRITISH PLANT-GALLS 179 
Diptera 
Homop- 
tera 
Fungi 
Diptera 
Homop- 
tera 
Fungi 
URTICACEAE 
Urtica dioica Linn. 112. Great Nettle. 
Unilocular, rounded, greenish-white swelling, 3 to 8 mm. 
in diameter, usually at the base of the leaf, with an 
elongated aperture on the upper surface ; becoming violet 
at maturity. Sometimes occurring on the stem and the 
flower stalks. Larva white. M. E. 
PERRISIA URTICAE Perris 312 
Syn. Dasyneura urticae Perris. 
Connold, Veg. Galls, pi. 90; Plant Galls, fig. 101. 
Houard, No. 2095. 
At the extremity of a branch. A bunch of leaves with 
involuted margins. 
Aphis urticae Fabr. 313 
Buckton, ii., 50. Houard, No. 2094. 
Leaves deformed and curled. 
Trioza URTICAE Linn. 314 
Connold, Plant Galls, fig. 162. Houard, No. 2097. 
Elongated swellings on the stems, with much thickening 
and distortion. The orange-yellow aecidiospores appear 
on roundish yellow spots thereon, also on the leaves. May 
and June. (Plate XVI. 2.) 
Aecidial stage of Puccinia CARICIS Schum. 315 
Syn. Aecidium urticae D. C. 
Plowright, p. 169. Connold, Plant Galls, p. 257. 
Urtica urens Linn. 108. Small Nettle. 
Swellings at the base of the leaf. See No. 312. 
Perrisia urticae Perris 316 
Houard, No. 2099. 
Leaves crumpled and deformed. 
Trioza urticae Linn. 
Houard, No. 2100. 
3 l 7 
POLYGONACEAE 
Polygonum convolvulus Linn. 31. Black Bindweed. 
Blossom swollen, containing the dark violet mass of 
teleutospores. June to September. 
Ustilago utriculosa Nees 318 
Syn. Ustilago utriculosa Tulasne. 
Plowright, p. 280. 
