The Scottish Naturalist. 283 



Prof. J. W. H. Trail, in the Transactions of the Natural History 

 Society of Aberdeen, published two articles, the first entitled Galls 



and their Makers in Dee, 1878, pp. 55-83, and the second, 



Scottish Galls, 1885, pp. 35-55. They contain the same 

 information as the articles in the " Scottish Naturalist/' the second 

 paper being, in fact, a reprint of those in vol. I. of the New Series 

 with a considerable appendix. Both articles relate especially to 

 galls and gall-makers in the north-east of Scotland ; indeed, that 

 of 1878 is restricted to the province Dee, including almost all 

 Aberdeenshire, and part of Kincardineshire. 



In what I have now to communicate, I propose to bring to- 

 gether, in readily accessible form, what is known in regard to 

 Dipterous Gall-makers and their Gal'Ts in Scotland ; and, neces- 

 sarily, my paper will rest very largely upon the information 

 contained in the articles just mentioned. 



I must now pass to a brief general review of the great groups 

 under which the gall-making Diptera of Scotland naturally fall, 

 and also of the general characteristics of their galls ; and I shall 

 follow this with a descriptive list of the galls of Diptera yet known 

 from Scotland ; adopting the systematic order of the plants as 

 more convenient than that of the insects, inasmuch as there are yet 

 many galls, the makers of which have not been reared, and are, 

 therefore, still uncertain. The groups of Diptera among which 

 Scotch gall-makers exist are, (1) Muscidse, under which come 

 two species said to be gall-makers, viz., Lauxania aenea, taken in 

 "Dee" by Dr. Vice; and a species of Anthomyia ?. Lauxania 

 aenea Meig. is said by Winnertz to gall the ovaries of Viola tricolor 

 and of its sub-species Viola arvensis ; but I am not aware that this 

 has been confirmed in Britain, though the fly is not scarce here. 

 It is about J to |- inch long, dark, metallic green, with reddish - 

 yellow legs and antennae ; in form it is not very slender. The 

 Anthomyia is uncertain, being known only in the larva state; 

 it lives in a kind of gall, formed on fronds of the Lady Fern and the 

 Shield Ferns by rolling in the apical half of the frond into a loose 

 ball. The larva feeds on the inner portions, which become black 

 and decayed ; and when full fed it burrows into the ground. The 

 larvae in the galls on these ferns are like those of Anthomyia (a 

 genus a good deal like the house fly) ; but in the meantime their 

 identification remains uncertain. 



II. The Trypetidse, which form the. next group, are closely 



