HARDWICKE'S SCIENCE-GOSSIP. 



2 35 



paucity of CEcidium berberidis in this county generally. 

 If Mr. Williams finds the Puccinia, caricis I would 

 recommend him to gather a handful or two of the 

 affected carex and place it amongst some nettles 

 where it will not be disturbed during the winter, and 

 no doubt next year he will be rewarded by gathering 

 the cecidium in abundance. — Charles B. Plowright, 

 7 King Street, King's Lynn. 



Fasciated Stems. — These are not less common 

 than pointed out by Mr. Kidd, in his interesting 

 article. Some time ago, I received a stem of wood 

 spurge {Euphorbia amygdaloides), which was strik- 

 ingly fasciated. Last spring a scape of cowslip 

 \Pri mulct veris), was brought me from Devonshire 

 which was very broad and much flattened, and which 

 bore more than one hundred flowers, some of them 

 imperfect. Soon after this, I gathered at Caterham a 

 smaller, but similar stalk of the same species, contain- 

 ing forty-six flowers. I have before me a well- 

 marked example of the same phenomenon in thistle 

 \Carduus lanceolatus), which I obtained in Clapton 

 a few days ago. The greater diameter of stem is 

 four times the smaller, and the flowerhead, crowded 

 by suppression of the peduncles into a knob rather 

 less than my two fists, are upwards of forty in 

 number, some at the top being only partly developed. 

 And, lastly, there are in my garden now, 1st of 

 September, four hollyhock stems in all of which the 

 flattening of stem and increase in number of flowers, 

 with crowding, are as noticeable as in the thistle. — 

 y. T. Powell, Lower Clapton. 



Uromyces Po^e.— After reading Mr. Plowright's 

 interesting communication on Uromyces pocv, I was 

 reminded of two places where I knew the CEcidium 

 had been growing in the spring ; one at Harborne, 

 where it occurred on Ranunculus repens, the other 

 at Salford Priors, where it was found on R. Ficaria. 

 I visited both these places, and, needless to say, 

 found the Uromyces potc in plenty on the leaves of 

 Poa immediately surrounding the ranunculus plants. 

 To those who still deny the fact of heteroecism, it 

 •may be as well to point out that the evidence is 

 cumulative. Of course mistakes may and must 

 occur in associating the CEcidia with their respec- 

 tive Uredos and Puccinias, but observation will 

 gradually correct these errors. But to the reality 

 of the association, every fresh instance of inductive 

 •discovery, such as has taken place in regard to 

 Uromyces pocc, bears increasing testimony. I may 

 add that I can find no trace of the Uromyces 

 where there is no ranunculus, even in the immediate 

 vicinity of the places which I have mentioned. — 

 W. B. Grove, B.A. 



Drying Flowers to retain the Colours. — 

 One of our correspondents suggests a simple plan to 

 retain the pink, blue and other colours of flowers 

 when drying in the herbarium press. We have tried 



the plan successfully, and are glad to make it better 

 known. It is simply to brush over the petals (with 

 a fine camel-hair brush) a weak solution of alum ; in 

 nine cases out of ten it never fails, and the specimens 

 so preserved are really beautiful. 



The Flora of Wrotham. — We have received 

 from the Rev. J. W. Ewing, Boro' Green, Sevenoaks, 

 a neatly published little brochure of 50 pp., giving 

 a very full and complete list of the flowering plants in 

 the neighbourhood of Wrotham. There are also 

 appended lists of birds, butterflies, and moths. 



Lightning and Trees. — It is no uncommon 

 thing to find the lower parts of a tree cut up by 

 lightning, while the upper portions and the highest 

 branches are hardly, if at all, affected. Oaks, how- 

 ever, appear to be an exception to this general rule. 

 Professor Colladon (who has long been studying the 

 phenomenon in Switzerland) is of opinion that this 

 partial attack is due to the fact that the upper parts 

 of a tree contain more sugar than the lower, sugar 

 being a good conductor of electricity. 



Dr. Hermann Mueller. — It is with much pain 

 we have to record the death of this eminent naturalist, 

 whose researches have been of such an original 

 character as to form a new line of departure in botany 

 and entomology. He was the first authority in one 

 branch of natural science, the relation of insects to 

 the fertilisation of flowers. A zoologist by profession, 

 he paid special attention to, and greatly elucidated, 

 those points in the structure of insects which adapted 

 them to carry pollen from flower to flower, and thus 

 secure cross fertilisation. His two chief works were 

 "Die Befruchtung der Blumen durch Insekten" (a 

 translation of which, with a preface by Charles 

 Darwin, was recently published by Messrs. Mac- 

 millan), and " Alpenblumen ; ihre Befruchtung durch 

 Insekten." The genesis of the colours of flowers was 

 a subject which he had worked out with great care. 



GEOLOGY. 



The Glacial Period in America.— Professor 

 Lewis, an American geologist, states there is every 

 proof that, ages ago, the great Greenland glacier 

 crept down so as to overspread the north-eastern 

 parts of America, and the north-western parts of 

 Europe. He treats of this northern glacier as a sheet 

 reaching from Greenland to St. Louis, and from 

 Alaska to New Jersey ; so thick as to overtop 

 Mount Washington ; he estimates its thickness in 

 New England at 5000 feet, and gives his reason for 

 supposing that the melting of this glacier need not 

 be longer than 10,000 to 15,000 years ago. 



The Brontosaurus.— One of the most gigantic 

 and remarkable of the extinct American animals 



