Fauna of a Horse-Chestnut Tree (Aesculus hippocastanum). Dipterous Larvae and their Parasites

Abstract

The insect fauna of tree wounds with sap-exudations or “slime flux,” as well as that of the water-filled hollows of trees, has already attracted the attention of entomologists and several interesting life histories of insects have been recorded from these media. In the present paper I propose to deal with the fauna of only one tree, a horse-chestnut standing on the Downing site between the School of Biochemistry and the Molteno Institute. For several years this tree has supplied me with very rich material for the study of Dipterous larvae and their parasites. Unfortunately, this study recently came to a natural end when this tree, with several others, was cut down to make place for a new building. This fact justifies the publication of the present records of observations collected during several years, although I do not consider them as complete. The most interesting feature of our horse-chestnut tree was the presence of two kinds of lesions each harbouring a different fauna: (A) a sap-exudating or “ slime flux ” wound, and (B) a waterfilled hollow or reservoir.