146 BRITISH OAK GALLS. 
OTHER GALLS ON THE BRITISH OAKS NOT 
PRODUCED BY CYNIPIDA. 
Gall-pits caused by females of Asterolecanium variolosum, 
Ratzeburg. 
(Plate LXIT.) 
Asterolecanium quercicola, Sig.; Planchonia fimbriata, Fons.; 
Coceus variolosum, Ratz.; C. quercicola, Planchonia quercicola, 
Bouch., Maskell, Froggatt; Asterodiaspis variolosus, Boas; 
“A. quercicola, Bouch, Newstead. 
English name of gall.—‘ The Pit-making Oak Coccid.” 
Position of gall.—On small twigs of Quercus pedunculata and 
Q. sessiliflora. 
Manner of growth.—Single, gregarious, coalescent. 
Colour.—Slightly paler than the surrounding part of the twig. 
Average external dimensions of a mature gall-=pit.— 
Height, 1mm.; length, 3mm.; breadth, 2mm. 
May be sought during the months of May to October. 
These peculiar circular, but mostly ovoid, swellings 
on oak-twigs result from external influence. 
They are due to the presence of female Coccide. 
These msects pass their life in a fixed spot on the 
twig, and as the result of their method of feeding, and 
other causes, irritation is set up in the plant tissues 
which produces elevated margins of bark around each 
insect. 
The pits thus formed are relatively very deep, the 
margins rising sufficiently high to conceal the ventral 
rim of the insect’s test. 
These gall-pits may be found in many districts in 
great numbers. Usually on tender and growing twigs 
of small scrub-oak bushes among the low and straggling 
herbage of a roadside bank ; but they not infrequently 
appear also on terminal twigs of young trees in woods. 
Tits are extremely fond of the insects, and search 
most diligently for them. When a twig dies, either 
naturally, or from being severed, the margins of the 
gall-pits diminish considerably. 
