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Exhibitions, 



The President exhibited a box of galls, which had been forwarded to him from 

 Germany, together with the miikers of many of them, named in accordance with the 

 nomenclature adopted in Hartig's work on gall insects. One of the species was 

 Cynips Kollari, hitherto erroneously called in this country C. lignicola. Of this spe- 

 cies the President remarked that about three years ago it appeared in the woods near 

 London, especially on the north side, in very large numbers ; but in the second year 

 of its appearance the tomtits had discovered that each gall contained a fine fat 

 grub, and the result was that it was now difficult to obtain a perfect gall. Mr. 

 Walker corroborated Mr. Smith's account both of the appearance and the approxi- 

 mate extermination of the species in the woods near Highgate ; and Prof. Westwood 

 expressed a hope that the fact would be made known as widely as possible, since it 

 afforded an additional argument to the many already produced in opposition to the 

 indiscriminate slaughter of small birds. 



Prof. Westwood exhibited specimens of Acarus domesticus, DeG. (A. Siro, Linn.), 

 found by Dr. Maddox, of Woolston, Southampton, in a nitrate of silver bath prepared 

 for photographic purposes ; and suggested that Mr. Andrew Crosse's wonderful crea- 

 tion of Acari might probably be explained on the hypothesis that, in that case as in 

 this, the insects had been attracted by some of the chemical ingredients employed. 

 He also exhibited some photographs of insects sent to him by Mr. Dale, the execution 

 of which was so good that, notwithstanding a certain haziness, the specific distinctions 

 of even small species were recognizable: many of the insects photographed were 

 gummed on card, which spoiled the effect ; but when they were pinned high, and had 

 the wings flat and horizontal, the result was so successful that the Professor thought 

 that for large insects, and especially for Neuroptera, photography might well be 

 employed for the publication of figures ; but that for smaller species it would perhaps 

 only be useful in taking representations, from which the draftsman might afterwards 

 make magnified drawings. 



Prof. Westwood also exhibited a continuation of the series of illustrations of the 

 economy and transformations of insects, presented to the new Museum of Oxford by 

 S. Stone, Esq., of Brighthampton, near Witney. Amongst them were specimens of 

 the preparatory and perfect states of several species of dragon flies ; the cocoons and 

 perfect states of Trichiosoma Lucorum and its parasites (two species of Ichneumonidje), 

 and Prof. W. stated that many years ago he had reared a perfect imago of this Tri- 

 chiosoma from a cocoon which also contained within it a few cocoons of a small 

 ichneumon, which had consequently not succeeded in killing the Trichiosoma larva. 

 Also several other small species of Tenthredinidse and Crabronidae, reared from bram- 

 ble twigs, the pith of which had been bored into by the larvte of the former, and by 

 the parent wasps of the latter ; also several species of galls and other insects, and 

 various leaf-mining insects of different orders, including a species of Orchestes ; also 

 the cocoon and imago of a species of Hemerobius, and the pupa-skin and imago of a 

 Raphidia, the pupa having been found in a burrow in the pith of a twig, where pro- 

 bably it had fed upon the larva by which the burrow had been made. Mr. Stone had 

 also forwarded a large number of illustrations of the operations of leaf-mining insects 

 of different kinds ; and Prof. Westwood added that he had also received from Mr. 

 Varney a series of specimens, carefully prepared, of leaves of a great number of 

 garden plants of different kinds, which had been attacked by the leaf- cutter bee. 



