56 . 
falls off like a lid when the occupant is mature ; of this last class 
we have no representatives in this quarter. The second class 
are formed by beetles, flies, sawflies and gallflies, and are 
always tenanted by larve. 
The first class embraces a somewhat heterogeneous assemblage 
formed by beetles, flies, hemiptera (chiefly aphides), and mites, 
and often are tenanted by the mature insects as well as by the 
larvae. The 1st class is subdivided— 
a. Galls which consists only of deformed outer structures 
of the plant, usually the work of gall midges, of mites, or of 
aphides. 
b. Galls which are situated in the inner tissues of the plant, 
but have not a closed chamber, though often there is hardly a 
trace of an opening. They are caused by gallmidges (Cecid- 
omyide) by Trypetide, or by Aphides. 
2. The closed galls are also divided into two great groups, viz., 
ce. With a clearly defined larval cell or cells, the wall consisting 
of a defined tissue harder and closer than the rest of the gall. 
The makers belong to the gall-flies (Cynipide). 
d. With undefined larval-cell, there being no distinct tissue 
surrounding the cell; these galls are the work of beetles, saw- 
flies (Tenthredinidee), or gall-midges. 
Galls may also be regarded from the side of the plants on 
which they occur; and this mode of looking at them has the 
advantage of aiding beginners in their search for these produc- 
tions, and in identifying them when found. I shall, there- 
fore, follow the order of the plants (in English floras) in the 
arrangement of these notes, but will add a list of the gallmakers ~ 
under their different orders as far as I have been able to identify 
them. The localities mentioned in each case are those in which. 
I have myself gathered the galls, unless otherwise stated. 
Nat. ORDER CRUCIFERZ. 
Brassica oleracea L, forma acephala (= Kail.) 
», campestris L (= Turnip.) 
»»  Sinapistrum Boiss (= Wild mustard or Charlock.) 
Thlaspi arvense L (Field Penny-cress.) 
Raphanus Raphanistrum L (—Runchock or Wildradish). 
In all these species the galls are alike, being hemispheres $—4 inch 
diameter, projecting from the root or from the stem, just above or 
below the surface of the ground. They have thick fleshy walls 
surrounding a central cell. Sometimes two or more are united. 
They are formed by beetles, viz., Ceuthorhynchus sulcicollis, Gyll, and 
its allies. All of them are common near Old Aberdeen, those on 
cabbage and turnips in winter and spring, on the other plants 
in June and July. 
Nat. OrpD. CISTINER. 
Helianthemum vulgare Gartn, (= Common rock rose) galls of Dizplosis 
Helianthemi, Hardy (gall-midge) terminal, ovate, rather over j 
