154 TRANSACTIONS OF THE 



our potato crop. Fungi have been found in very peculiar situa- 

 tions, such, as in the eggs of birds, the seeds of plants, and the 

 brains of animals. He then gave a short description of the more 

 important and conspicuous groups — Agaricini, Polypori, Hydnei, 

 Auricularini, Clavarici, and Tretnellini. The paper was illustrated 

 throughout with numerous diagrams and specimens. Among the 

 specimens was a very large plant of Polyporus hetulina. It may 

 be mentioned here that Dr. Cooke, a great authority on the sub- 

 ject, says that fungi do not grow in winter. This cannot be the 

 case, as most of the specimens exhibited were gathered in Feb- 

 ruai-y, and v/ere growing in profusion in Cadder Wilderness. 



22nd February, 1876. 

 Mr. James Allan, Vice-President, in the chair. 



SPECIMENS EXHIBITED. 



By Mr. E-. H. Pater son. — Some splendid specimens of corals, 

 sponges, and Sertularidse from New Zealand. 



PAPER READ. 



On Dipterous Gall-makers and their Galls. By Mr. F. G. Binnie. 



Plants and animals, in addition to the ordinary and normal 

 features of their growth, exhibit, not unfrequently, diseased 

 enlargements and out-growths. These irregular and superinduced 

 formations, according to the particular characters which they 

 assume, are known as warts, excrescences, tumoixrs, galls, and so 

 on. That change of structure which is brought about by the 

 puncture or irritation of some animal, usually an insect, is specifi- 

 cally known as a "gall." 



1 need scarcely remark that animals as well as plants are sub- 

 ject to galls ; I will only instance the tumours produced beneath 

 the skin of our domestic ox by the bots or larvae of (Estrus Bovis, 

 De Geer. These abnormal swellings have, however, in animals a 

 very uniform character, and are generally included under the term 

 "tumour;" the designation "gall" being more particularly and 

 usually applied to the diseased structures produced on plants. In 

 such restricted sense I use it in this paper. 



