The Scottish Naturalist. 323 



one larva. These galls occur along with the former 

 (T.S.N, I, 157; T.A., I., 64-65 ; B.I, 161). 

 A. Millefolium (Yarrow or Milfoil). 1. Galls of Hormomyia 

 Ptarmicce Vail., similar to those on A. Ptarmica, but 

 usually smaller, and wanting the reddish tinge. I have 

 found these galls near Aberdeen. (T.S.N. , I., 157; 

 T.A., I., 65.) * 



2. Galls of Hormomyia Jlillefolii H.Lw., occur singly in the 

 axils of the leaves, or in the lower part of the stems, at 

 or below the ground, in groups of two or three. They 

 are ovate or somewhat triangular, about l by J inch, 

 smooth, naked, green, or pufplish-brovvn, blunt, splitting 

 open at the top, to set free the larva ; the walls are 

 thick and fleshy, and enclose a small cavity. I have 

 found this gall in autumn near Aberdeen, and elsewhere 

 on Deeside, and also in Perthshire ; and Mr. Binnie 

 states that it occurs near Glasgow. (T.S.N., I., 157 

 T.A., I., 65 ; B.I., 161.) 



Artemisia Abrotanum (Southern Wood). On this plant I 

 found galls in a garden in Old Aberdeen, in October, 

 1884, upon the younger leaves of the twigs. Numerous 

 galls occur on each leaf. They are nearly cylindrical, 

 attached to the surface of the leaf by one side, free and 

 conical at the end next the tip of the leaf, about il by 

 -| mm. ( T \- by T \j- inch), slightly yellowish or dull reddish- 

 green, but otherwise the surface is like that of the leaf. 

 The free wall is very thin. Each gall was filled by one 

 orange-red larva of a midge. Several of the flies, both 

 male and female, emerged in spring from galls kept all 

 winter in a box. They proved to belong to a previously 

 unnamed species of Hormomyia. I have named them 

 H. Abrotani. (The insect is described in the Scottish 

 Naturalist, n.s., vol. 11., p. 250.) 



Senecio Jacobsea (Ragwort) and >S r . aquaticus frequently have 

 the flow r er-heads swollen to twice their natural size : and 

 they remain green, or only show the tips of the corolla. 

 A cavity is formed above the receptacle, in which lie 

 several reddish-orange larvae of Cecidomyia. I attributed 

 these galls, from which I have not succeeded in rearing 

 the makers, to C. Jacobean H.Lw. (T.S.N., VI., 15 ; T.A. 



