1887-88.] Galls of Norway. 209 



veins in the segments. They seldom exceed 4 mm. in length. 

 On section they are found to enclose a narrow irregular cavity, 

 filled with the minute worms. I have found these galls in 

 the Brenner Pass in the Tyrol, in very fine condition, as many 

 as twenty occurring on a leaf, two or three sometimes on a 

 single segment. I have looked for them in Scotland without 

 success ; but Mr Cameron told me that he had found them 

 in the neighbourhood of Glasgow. 



A. Ptarmica, Linn. — Ip 1878 I found, near Bergen, and 

 near Christiania, the galls of a midge {Hormomyia Ptai-micm, 

 Vail.) on Sneezewort Yarrow. They are inflorescences, which, 

 in consequence of the suction of the gall-makers, become 

 swollen, but remain abortive, and are covered with a coatino- 

 of pale woolly hairs. A section of the galled flower-head 

 shows numerous larvae of the gall-midge. These galls are 

 common in Scotland, and have been recorded from all the 

 countries of Central Europe. On the Norwegian examples 

 there also occurred small ovate galls in the axils of the 

 upper stem-leaves. They are nearly smooth, and are purple 

 in colour; but from observations on these galls, in Scotland, 

 where also they are associated with the galled inflorescences, 

 I believe that they are the work of the same midge, the 

 woolly coating being produced only in the inflorescences, 

 from the organs situated there. 



Hicracium murorum, Linn. — Near the Buarbrse glacier, in 

 Hardanger, last August, I gathered several leaves of a Hier- 

 acium, which appears to be this species, bearing galls of 

 Cccidomyia Hieracii, F. Loew { = C. sanguinea, Bremi, named 

 from the galls alone). The galls are mere low blisters in 

 the leaf-blade, slightly convex on the lower surface, but 

 almost flat above ; yet they are very conspicuous, since each 

 is situated in a dull red-purple spot, which is surrounded by 

 a border of reddish yellow. Seldom does a gall stand quite 

 alone ; far more often from three to ten are grouped so close 

 that the coloured spots touch or partially coalesce to form an 

 irregular line, sometimes near the midrib, sometimes near the 

 margin. Each spot is from 4 to 6 mm. across. When full- 

 fed the larvae burrow underground to become pupae. These 

 galls have been recorded from Austria, Germany, and France. 



H. corymbosinn. Fries. — In the Simodal, in Hardanger, last 

 August, I picked up two or three galls of Aulax Hieracii, 



