1885.] THE ENTOMOLOGIST. 263 



The jZntomologist. 



GALLS IN BEDFORDSHIRE. 



OBSERVANT residents in or visitors to the country will have 

 noticed that the oak trees are this year more than usually 

 burdened with galls of various kinds. Especially one kind of gall, 

 which resembles a small potato and grows at the ends and sides of 

 the twigs where leaf-buds ought to have developed, may be seen in 

 sreat numbers. A tree near Cardington looks as if it were laden 

 with fruit, so numerous are these injurious excrescences. The life- 

 history of the flies tliat produce these galls is — like that of many 

 of their kindred — exceedingly curious. It is only recently that 

 entomologists have correctly learnt what this life-history is ; but 

 they now know that the insect in question is one of those that exist 

 in two distinct forms, producing two distinct kinds of gall, the one 

 form of fly and gall alternating with the other. In the late summer, 

 the little gall-fly — Tcras terminalis — emerges from the potato-like 

 galls above mentioned, makes its way down to the roots of the tree, 

 and there lays in the bark of the roots eggs that produce small 

 reddish-green galls. In the winter — particularly if the weather be 

 open — from these galls there emerges another gall-fly — Biorhyza 

 aptcra — unlike its progenitor, and this climbs to the branches, and 

 lays eggs in the already formed leaf-buds. One entomologist 

 certifies that in the course of eighty-seven consecutive hours, he 

 observed a single individual gall-fly of this species lay 582 eggs in 

 two leaf-buds. As soon as the buds begin to swell, early in May, 

 those that have been made the receptacles for these eggs, instead of 

 developing into twigs, grow into potato-like galls, each containing a 

 number of grubs which in July issue in the shape of specimens of 

 the Tcras terminalis, and proceed, as stated above, to attack the root. 

 When a tree is infested so much as some we have this year seen, 

 there can be but little new wood produced during the season, and the 

 general health of the tree must be seriously impaired for the time at 

 least. — Bedfordshire Times and Independent. 



The Sieex Gigas. — Erom su.bsequent communications from Mr. 

 Eobertson, forester at Novar, Eoss-shire, it appears that the Sircoi 

 Gigas is the smaller insect of his former communication. Its boring 

 galleries in the pine bark and onwards, show how much damage 

 this small pest may effect on noble forests. 



