20 [Jut 
closely allied to, and yet quite distinct from, those produced in June. Out ( 
thousands of these autumnal flies examined by us, all were females, with not 
single male among them ; and we have experimentally ascertained, by colonizing 
number of these females upon isolated black-oaks known to be not previouel 
infested with oak-apples, that they cause apples to be generated in the followiu 
spring upon such isolated oaks. From oak-apples produced in this manner we hav 
bred two specimens of the spring foi-m (Q.-spongifica) of gall-fly which exists in bot 
sexes, and five specimens of the autumnal form (Q.-aciculata) which exists exclusiveh 
in the female form. Finally, treating these five autumnal specimens in the sami 
manner, i. e., placing them upon another isolated black-oak, we obtained galls i 
the following spring which produced two specimens of the spring form (Q.-spo^ig-ifica]' 
thus showing that the autumnal form sooner or later reverts to the spring fora 
Hence, as well as from other considerations, we may infer that the former is not 
distinct species, but a mere dimorphous female of the latter ; for otherwise on 
form could not generate the other. The bastard oak-apple matures like the pre 
ceding in June, but is found exclusively upon the red-oak (Quercus rubra). 1 
differs from the preceding in never reaching so large a size, in the central cell no 
being woody, but consisting of a mere shell which can be readily broken with th 
thumb-nail, and in its being only connected with the external rind by slendet 
radiating filaments. Males and females (C. Q.-inanis) absolutely indistinguishabl 
from the spring form of the preceding species, are obtainable from this gall i 
June ; but after repeated trials we have never succeeded in breeding from it t 
single autumnal female, and we do not believe that any such form exists. Hence 
and also in consequence of the very great dissimilarity of the galls, and thei 
always gi-owing upon distinct species of oak, we are compelled to consider thesi 
two gall-flies as distinct species, although when placed side by side the form 
generated in the spring are always exactly like each other." 
Mr. McLachlan exhibited all the forms of a small species of Termes brough 
from St. Helena by Mr. Melliss, and being the same to the ravages of which, ii 
that island, Mr. Layard called the attention of the Society in 1866 (Trans. Ent 
Soc. 3rd series, vol. v, Proo. p. xii). Mr. Layard stated that the insect had beei 
introduced in timber from the Coast of Africa, but Mr. McLachlan could no 
identify it with any described African species, and was inclined to consider it th( 
r. tenuis of Hagen, which inhabits the West Indies and Brazil. Considering tha 
St. Helena is a place of call for vessels from all quarters, there is no reason why i 
ehould not have originated from the West ; though one would naturally look t( 
Africa as its home, and from this cause he was inclined to think that the idea o 
its coming from thence had originated. It is an anomalous species in its structure 
in which it agrees with T. tenuis. Mr. McLachlan also exhibited a large number o 
small black Podurce placed in his hands by Mr. Henry Lee, and concerning whicl 
it was stated that they had been found at Hungerford, on the 10th April, on th( 
surface of a duck-pond, which they covered to such an extent as to give the ide£ 
that a bag of soot had been emptied over it. 
Mr, A. R. Wallace read "Notes on eastern Butterflies (Biadema)." 
Mr. Butler read " Descriptions of a new or little known forms of Diurnal 
Lepidoptera." 
