77 
irregular cavities, in which live multitudes of the mites. The 
galls occur at Ballater and at Inverurie. 
Abies communis L. (Spruce Fir), galls of Chermes (Adelges) Abietis, L. 
They are swellings at the base of the young branches (which are 
stunted) resembling small green cones (sometimes only one side of 
the branch, sometimes all round it), about 1 x 3 inch, or smaller; 
they are made up of imbricate leaves, which remain short, and 
become scale-like, ovate, and fleshy, and enclose between them 
small cavities in which live the Aphides. The galls remain on the 
tree for a long time in a woody condition with the scales gaping. 
They are abundant throughout ‘Dee,’ and are to be found ina 
fresh state in early summer. 
A smaller and more compact form occurs at the tips of the twigs, 
usually two or three occurring close together. It seems to be the 
gall of Chermes (Adelges) strobilobius, Kalt. 
Juniperus communis L. (Juniper), galls of Cecidomyia (Hormomyia) Juni-_ 
perina L. On the tips of the branches, in the form of an ovate cone 
composed of three modified leaves, which become scale-like, about 
1 x inch, or rather more, but retain their green colour; they 
meet closely along the edges; inside these are three other much 
smaller leaves, which enclose a cavity in which the larva lives. 
The galls retain their form when dry; they appear in. May and 
June, and the midges emerge in Juneand July. They are com- 
mon on Deeside from Banchory upwards, and also in Corgarff 
and in Strathdon. 
MONOCOTYLEDONS. 
Nat. ORD. GRAMINES. 
Agrostis canina L. Mr Walker, this summer, gave me a specimen of 
this plant, gathered by him near Kingcausie, on the main axis of 
whose panicle near the top, just where branches were given off, a 
swelling occurred ; the gall is very small, ;;—;'g inch, irregularly 
oval (including the base of the branches), naked, nearly smooth, 
and purple. It opens by a small hole on the upper surface among 
the branches. On section it was found to contain a pretty large 
irregular cavity, the sides of which bore transparent filaments 
and small warts. Careful examination of the single dried speci- 
men showed no occupants, but it is probably the work of mites— 
‘ Phytoptus. 
Triticum repens L. (Couchgrass). The gall is a cylindrical swelling at the 
tip of the stalk, composed of the closely imbricated leaf sheaths, the 
axis remaining very short; the gall reaches a length of 13 inches 
by 33;-3 inch in the middle, but tapers to each end. It usually 
emits several leaves; it is seldom less than six inches above ground. 
On section a small cell is found in the centre of the axis, enclosed 
* among the leaf-sheathes, and in it lives one white larva of Hury- 
toma, which insect is probably the maker of the gall. These galls 
appear in autumn in abundance near Aberdeen, and at Banchory. 
To rear the insect it is best to collect the galls in spring, as the 
larva passes the winter in them. 
Triticum junceum L. The gall is like that on T. repens in structure, but 
is stouter (1-14 x 2 inch), is less apt to emit leaves, and is usually 
close to the soil. It is abundant on the sandhills along the coast. 
ACOTYLEDONS. 
Nat. ORD. FILIces. 
Pteris Aquilina L. (Common Bracken), galls of Cecidomyia Pteridis Miill. 
’  _These are pitinules, one or both margins of which are revolute, 
