SCIENCE-GOSSIP. 



179 



a great degree of moisture is distinctly unfavour- 

 able to the production of fine autumnal leaf effects. 

 In fact, it has been frequently noticed in the 

 analogous case of flowers that an unusually dry 

 springtime causes petals normally white to assume 

 pinkish tints. The second point, the relative number 

 of stomata, demands more positive proof. I shall 

 adduce two instances : one where the tree is known 

 to flourish most luxuriantly in damp swamps or 

 moist localities, for example, the scarlet maple 

 (Acer rubrum) of the New England forests. 

 Evidently a tree like this, whose structure is 

 specially adapted to humid surroundings, will be 

 powerfully affected by any temporary deficiency in 

 the supply of water from without ; as a special 

 feature of its structure is that the transpiration 

 from its leaves is very great, the number of stomata 

 per square millimetre amounts to about four 

 hundred. Hence the requisite concentration of 

 the cell sap of its broad leaves is easily accom- 

 plished, and the colour effect of the surprising 

 blaze of its autumnal tints, once seen, is not 



readily forgotten. On the other hand, if we 

 consider the case of the common ash we discover 

 something very different. This tree also affects 

 moist situations, but it is not particular as to soil ; 

 its leaves are narrow and much divided, or 

 imparipinnate, therefore more liable to become dry 

 than if they were broader and thicker, but they 

 carry only about one hundred and fifty stomata 

 per square millimetre. Hence, in point of fact, 

 they do not readily lose their moisture. Save 

 under exceptional circumstances, they never at 

 any season exhibit any red or crimson coloration, 

 Moreover, as it so happens, the tannin of the ash, 

 unlike that of the maple, does not form coloured 

 anhydrides. Hence if any colour may be produced 

 in its leaves or flowers that would depend on other 

 causes and conditions than those which involve 

 its formation in the corresponding organs of the 

 other denizens of our woodlands. Further, the 

 tint would be like that of a dahlia rather than 

 that of a rose. 



Patterdale, Westmorland. 



THE BRITISH MYCOLOGICAL SOCIETY. 



HPHE Society held its annual week's fungus 

 foray this year from the 19th to 24th 

 September at Dublin, where the members were 

 the guests of the Dublin Naturalists' Field Club. 

 The energetic and indefatigable local secretary, 

 Professor T. Johnson, D.Sc, is heartily to be 

 congratulated on the excellent programme of 

 arrangements that he made for the excursions, 

 and the subsequent investigation of the finds. 



On Monday, September 19th, the members 

 assembled at the Botanical Rooms, in the Science 

 and Art Museum, Kildare Street, which had been 

 kindly placed at their disposal by the Director, 

 Colonel Plunkett ; but as no specimens had arrived 

 for identification, a preliminary ramble was or- 

 ganized to Howth. A list of " The Fungi of the 

 Counties of Dublin and Wicklow," by our member, 

 Mr. Greenwood Pirn, M.A., reprinted from the 

 "Irish Naturalist" for August, 189S, was pre- 

 sented to each member with the injunction to go 

 one better, and keep our motto ever to the fore, 

 viz., " Recognosce notum, ignotmn i?isfice." Howth 

 demesne proved to be a most suitable hunting- 

 ground, and seemed not to have suffered much 

 from the prolonged drought. Numerous additions 

 to the list were recorded, amongst which we may 

 enumerate a pretty resupinate Bydnum, H. ndum 

 Fr. ; one of the scarce tubers, Hydnotrya tulasnei 

 B. and Br. ; a rather uncommon Navcoria, N. 

 erinacea Fr. ; and a group of the horrent Lepiota, 

 L. acutesquamosa Weinm. Mr. R. LI. Praeger, 

 M.R.I.A., President of the Dublin Naturalists' 



Field Club, received the members in the evening 

 at the Botanical Laboratory, Royal College of 

 Science. The work of naming the specimens was 

 at once proceeded with, and a large collection of 

 fungi was placed on exhibition at the Museum 

 during the course of the week. Mr. Swann, F.L.S., 

 exhibited a splendid series of photographs of the 

 Saprolegnieae, which were of great interest, and 

 contained at least one new to science. 



On Tuesday, September 20th, Powerscourt 

 demesne was visited, but the estate had suffered 

 from the long drought, and only a few rarities 

 were encountered, such as the encrusting polypore, 

 Polystictus wynnei B. and Br., and growing on 

 fallen holly - leaves was the pretty Marasmius 

 hudsoni Pers., whose pileus and stem are covered 

 with long spreading hairs. The club dinner was 

 held in the evening at Russell's Hotel, and 

 universal regret was expressed that their President, 

 Mr. George Massee, F.L.S., F.R.M.S., was un- 

 avoidably prevented from presiding. In his 

 absence the members felt themselves adequately 

 presided over by the acting president, Mr. C. B. 

 Plowright, M.D., who subsequently read an 

 important address at the Lecture Theatre of the 

 Royal College of Science, entitled, " Notes and 

 Comments on the Agaricineae of Great Britain." 



On Wednesday, September 21st, the morning 

 was devoted to the determination of the speci- 

 mens collected and also of consignments of fungi, 

 which now came in from all parts of Ireland. In 

 the afternoon a search at Brackenstown, near 



