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dead branches, from Ashtead Woods. Tt is interesting as being one 

 of the lowest forms of the Hymenomycetes, the order which in- 

 cludes the mushrooms and toadstools. In the Tremellinfe no 

 portion of the plant is specialized for spore-production, the entire 

 surface producing spores mounted upon basidia in twos and fours, 

 A very small percentage of the bulk consists of solid matter, the 

 remainder is water, and in dry atmospheric conditions the plant 

 shrivels into a mere film of horny gelatine, which revives, however, 

 with the recurrence of dampness. 



He also showed an apterous form of long-horned grasshopper 

 from South Africa — Hetrodes petersi, female. Both sexes, he 

 believed, were apterous, and it was remarkable that in this con- 

 dition the " ears " in the tibiae of the forelegs are retained. 



Mr. A. E. Gibbs exhibited the two largest species of sawfly 

 [Sire.v) inhabiting the British Isles, and read the following notes on 

 them and the parasite Wiyssa persiiasoria : — 



*' The giant saw-fly and its parasite. — About two years ago I 

 drew the attention of members of the Society to the infestations of 

 two of our British species of giant saw-flies which occurred at St. 

 Albans in 1903. In that year a large number of specimens of Sirex 

 noctiiio, Fabr., appeared in the St. Albans Technical School, and 

 were ascertained to be emerging from a trunk of silver fir which 

 had been bought from a local dealer and was being cut up into 

 planks for the use of students in the wood-working classes. The 

 tree was extensively tunnelled by the larvae, and the instructor very 

 kindly put the wood aside for observation. Numerous imagines 

 appeared, and we used to catch them on the windows in the morn- 

 ing when they were trying to escape. Strangely enough, my atten- 

 tion was called at the same time by the late Mr. F. G. Kitton to 

 the appearance in his wood-cellar of numerous specimens of the 

 other large species — Sirex f/ii/ns, Linn. These were emerging from 

 the trunk of a fir tree which had grown on his lawn and had been 

 felled and cut up for firewood. I subsequently made up a museum 

 case with specimens obtained from these sources, showing the life 

 history of at least one of the species — S. noctiiio. The blocks of 

 wood show very well the way in which the larvfe bore their tunnels 

 in the solid timber, pupating in them, and eventually making their 

 way out as perfect insects. To-night I have to show you a creature 

 which is a parasite on the giant saw-fly, and which may therefore 

 be regarded as a useful insect. It is called Rhysaa persuasoria, Linn., 

 and the specimen I exhibit was sent to me by Mr. Charles Oldham, 

 having been taken in Berkhamsted, in July, by Mr. Edward Popple. 



