CATALOGUE OF BRITISH PLANT-GALLS 149 



Dipteia Leaf margin rolled inwards near the petiole. Rare on 

 this species of Willow. See No. 93. 



Perrisia marginemtorquens Winn. 135 



MacDougall, Journ. Bd. Agric, Oct., 1905. Connold, 

 Plant Galls, fig. 350. Houard, No. 807. 



Ovoid or spherical swelling, i to 5 mm. in diameter, on 

 both surfaces of the leaf, yellowish-green or pale yellow, 

 often tinted with violet or reddish-purple above. Gre- 

 garious or coalescent. Opening inferior, rounded, larval 

 cavity containing a single larva, white at first, then orange, 

 red at maturity. M. E. 



OUGOTROPHUS CAPREAE Winn. 1 36 



Syn. Hormomyia capreae Wtz. 



Connold, Veg. Galls, pi. 95; Plant Galls, fig. 272. 

 Houard, No. 812. 



Terminal leaves shortened, forming a rosette. See 

 No. loi. 



Rhabdophaga rosaria H. Low 137 



MacDougall, Journ. Bd. Agric, Oct., 1905. Houard, 

 No. 784. 



Fusiform swellings on one-year twigs. See No. 95. 



Rhabdophaga salicis Sch. 138 



MacDougall, Journ. Bd. Agric, Oct., 1905. Connold, 

 Veg. Galls, Pis. 26, 27 ; Plant Galls, fig. 269. Houard, 

 No. 800. 



.. Stem more or less swollen. See No. 94 and Plate IX. 10. 



Rhabdophaga saliciperda Dufour 139 

 MacDougall, Gall- Gnats on Osiers and Willows, Journ. 

 Bd. Agric, Oct., 1905. Houard, No. 798. The galls de- 

 picted on Plates XXVI. and XXVII. of Connold's "Vege- 

 table Galls," and on Fig. 269 of " Plant Galls," are caused 

 by the presence of Rhabdophaga salicis Sch., not R. salici- 

 perda, as therein stated. 



Acaxi Pedunculated yellowish or reddish pubescent pustule 



on the upper surface of the leaf. The interior may be 

 either subdivided by projections or quite smooth, Aperture 

 inferior, surrounded by hairs. Gregarious or coalescent. 



Eriophyes tetanothrix Nalepa 140 

 Connold, Veg. Galls, pi. 66; Plant Galls, fig. 271. 



Smooth pustular growth on the leaf, showing equally 

 on both surfaces, yellow or red. Interior smooth, or 

 subdivided by excrescences from its walls. Gregarious 

 or coalescent. 



Eriophyes salicis Nalepa 141 



Houard, p. 146. There is some doubt concerning the 

 species of Eriophyes responsible for this gall and the 

 preceding one. 



