SCIENTIFIC COMMITTEE, DECEMBER 15. 



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solely with minerals. Dung will largely increase the yield of stem and 

 leaf in all, but does not materially increase the yield of seed. If, therefore, 

 seed be required, grow on poor chalky soil without dung ; but if fodder 

 is required, dung may be profitably used as well as minerals. The 

 experiments also show the great use of the Vetch in ameliorating the soil, 

 greatly enriching it, and, at the same time, cleaning it very economically. 

 It is suggested that garden plants, having been for many generations 

 forced to an unnatural extent, are not able to adapt themselves to different 

 conditions of soil, &c. ; whereas field crops, which have had to seek for 

 food to a large extent, are able to develop specially well-formed roots, 

 which easily absorb water and such phosphatic, potassic, and other mineral 

 plant-foods as are available, and on these roots are developed large numbers 

 of nodules, by means of which an ample supply of atmospheric nitrogen 

 is assimilated. 



Scientific Committee, December 15, 1903. 

 Mr. A. D. Michael, F.L.S., in the Chair, and eleven members present. 



Violets diseased. — Mr. Worsley showed specimens which Dr. Cooke, 

 V.^I.H., pronounced to be attacked by Urocystis violce, recently figured 

 in the Journal, vol. xxvii. p. 16, pi. i. fig. 19. 



Longevity of Fern Spores. — A communication was received from 

 Mr. H. Coleby, Wargrave, describing an instance of a piece of a stem of a 

 Dicksonia, possibly twenty years old, on which, when broken off and 

 kept moist, seedlings of Gymnocjramma aurea began to appear. It was 

 suggested that the spores of the latter had lain dormant for that length 

 of time. 



Mr. Druery, Y.M.H., contributed the following note : " I have raised 

 Ferns from spores seven to eight years old. The conditions mentioned by 

 Mr. Coleby strike me as being exactly such as to maintain the power of 

 germination for a very long time — i.e. absence of stimulating moisture or 

 warmth. I have no doubt that the Fern arose from dormant spores. It 

 is remarkable that only one kind of Fern germinated, though we must 

 assume that other Fern-spores were present on the old Dicksonia stem." 

 It was suggested, however, that the Dicksonia stem might have been 

 previously utilised for growing only the Gymnocjramma. 



Ashicood with Grubs. — Specimens were received from Mr. G. Gregory, 

 Croydon, with live grubs two years after the tree had been cut down. 

 The wood outwardly showed no signs, but on being sawn asunder both 

 dead and living grubs were frequently found. Mr. Saunders contributed 

 the following observations : " The insects found in the Ash timber are 

 beetles belonging to the family of Longicorns, and to the genus Clytits, 

 but not being an English species, but probably American, I have not 

 yet been able to obtain the specific name. The grubs of these beetles are 

 sometimes very long-lived, and they remain for years in wood where their 

 presence is quite unsuspected. A specimen of Longicorn beetle has been 

 known to emerge from furniture, the wood of which was felled twenty- 

 eight years previously. It is now supposed that the grubs which take 

 such a long time in undergoing their metamorphoses have been hatched 



