14 The Ottawa Naturalist. [April 



ARTEMISIA CAUDATA. 



Oval, woolly, apical or lateral bud galls with a diameter of 1 to 

 1.5 cm. and consisting of a series of oval cells, each with a length of 



about 2 mm. and with numerous long fibers Woolly wormwood gall, 



Rhopalomyia ?alticola Ckll. 



ARTEMISIA FORWOODII ( ? CANADENSIS) . 



Globular, woolly galls with a diameter of about 1 cm. 



Woolly wormwood gall, Rhopalomyia alticola Ckll. 



ARTEMISIA ERIGIDA. 



Fusiform flower or leaf bud galls, length 4 mm., also occurs on 

 A. filifera Rhopalomyia betheliana Ckll. 



ARTEMISIA GNAPHALODES. 



Irregular, lobulate, polythalamous, white, pubescent gall, diameter 



1 cm. Rhopalomyia gnaphalodis Felt. 



ARTEMISIA HETEROPHYLLA. 



Ovate, thin-walled, oblique leaf galls, length 1 mm., also breeds 

 in apparently normal flower buds Diarthronomyia occidentalia Felt. 



ARTEMISIA SP. ( WORMWOOD). 



Deformed flower heads, length 10 mm., diameter 5 to 6 mm. 

 Wormwood flower midge, Rhopalomyia coloradella Ckll. 



Bud galls presumably Asphondylia artemisia Felt. 



A bud deformation of black, globose or densely crowded fila- 

 ments Eriophyes sp. 



Ovate masses of linear, modified leaves occurring on the branch- 

 lets, length of mass 1.5 cm., diameter 5 to 7 cm Eriophyes sp. 



Subconical, short-wooled, yellowish gray, axillary bud gall, 

 length 2 cm., diameter 1 cm. Trypetid 



Globose, axillary, woolly bud gall, diameter 7 to 10 mm., the 

 hairs grayish white, short and thick Trypetid 



ARTEMISIA TRIDENT ATA (SAGE-BRUSH). 



Oval, bud-like flower gall the size of a pea. 



Rhopalomyia tridentatae Rubs. 

 Ovate, hard, thick-walled, yellowish brown bud gall, length 1.5 



cm., diameter .8 cm. Trypetid. 



Flask-shaped or subconical leaf gall, length 4 mm., diameter 



2 mm. Wormwood flask gall, Rhopalomyia ampullaria Felt- 



Oval, grayish or almost black, solitary or clustered gall on the 

 under side of the leaves, length 1.5 cm. 



Diarthronomyia occidentalis Felt 



Globose, variable, monothalamous or polythalamous leaf, bud or 

 rosette galls or a bladdery gall arising from the leaf, pubescence 

 variable, dimensions 3 to 15 mm Diarthronomyia artemisia Felt. 



Subglobular, brown, spongy apical gall, diameter 1.8 cm., possibly 

 identical with the preceding Cecidomyia sp. 



