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HARDWICKE'S SCIENCE-GOSSIP. 



BOTANY. 



The /Ecidium of Ranunculus Ficaria.— This 

 pretty /Ecidium is well known to many readers of 

 Science-Gossip as a microscopic object. It is 

 always interesting as being one of the first, if not 

 the very first uredine to make its appearance in 

 spring. Our knowledge of its life history, as derived 

 from works in the English language, has, however, 

 hitherto been either incomplete or inaccurate. Any 

 one who places a few ripe spores of this fungus upon 

 a drop of water on a glass slide, will find they germi- 

 nate in less than twenty- four hours. If the spores be 

 sown upon a healthy leaf of Ranunculus Ficaria, no 

 result ensues ; for the fungus is unable to reproduce 

 itself. As an ^Ecidium, as we have seen, the spores ger- 

 minate at once, and hence are incapable of reproducing 

 the /Ecidium in the following year even if the germ 

 tubes could be persuaded to enter the stomata of the 

 leaves of its host plant, which they cannot be. 

 Unless we are wholly occupied in the mere collection 

 of specimens of leaf fungi simply because they are 

 interesting microscopic objects ; it is quite worth our 

 while to inquire, how this fungus is kept alive from 

 the spring of one year to the same season of the 

 ensuing. There is not very uncommonly found a 

 species of Uromyces upon the same ranunculus, and 

 it has been suggested that because these two fungi 

 occur upon the same host plant, that therefore they 

 are states of the same fungus. This is, however, a 

 pure assumption, and is not borne out by experimental 

 culture. The ./Ecidium has never yet been produced 

 from the Uromyces, neither has the sowing of the 

 /Ecidiospore ever been followed by the develop- 

 ment of the Uromyces. It has however been shown 

 by Dr. Schroter, that if the spores of sEcidium 

 Ficaria be sown upon various species of Poa, a 

 Uredo, and subsequently a Uromyces, is the result. 

 This Uromyces differs from the Uromyces dactylidis, 

 Ottho (U. grammeum, Cooke), in various points, 

 but notably in the absence of paraphyses in its Uredo, 

 which the Uredo of U. dactylidis, always, possess. 

 Up to the present time Uromyces poa, Rbh., however, 

 has never been found in Britain. It must therefore 

 follow that, either the Teutonic savant is wrong in 

 his views of the life history of ^Ecidium Ficaria, or 

 else our British fungus must have a different life- 

 history. Believing, however, that Dr. Schroter was 

 right, I took an early opportunity this year of search- 

 ing carefully around any specimen of the /Ecidium 

 I came across upon the grasses, and was as a matter 

 of course rewarded upon the 25th May, by finding 

 the Uredo, and soon after the teleutospores of 

 Uromyces poa, Rbh., upon Poa trivialis. This is 

 one more illustration of the fact, that careful 

 experimental research is of infinitely more value than 

 the haphazard destructions of the closet naturalist, 

 however eminent he otherwise may be. If any of 



your readers are sufficiently interested in the subject, 

 I have no doubt they will find as much Uromyces 

 poa as they may want, if they only look for it on the 

 grasses (Poa) contiguous to plants of Ranunculus 

 Ficaria, which have earlier in the season been affected 

 with sEcidium Ficaria. Since writing the above, I 

 have received specimens of Uromyces poa from my 

 friends, Mr. H. T. Soppett, of Saltaire, and from 

 Mr. W. Marshall, of Ely, both of whom were kind 

 enough to search for the fungus in question in the 

 situation indicated above. — Charles B. Flowrigkt, 

 King's Lynn. 



Our Charas.— As one of the ' : few enthusiastic 

 and isolated workers " who for the last few years 

 have studied the life history of the Characese, and 

 assisted in working out their British distribution, I 

 most gladly welcome the article of Mr. Saunders that 

 appeared in your pages last month. Some of his 

 statements, however, appear to be slightly misleading, 

 and as the article is written for the purpose of helping 

 students in their study of these little known plants, 

 perhaps I may be allowed to compare them with my 

 own experience in collecting. Mr. Saunders says, 

 "it is equally useless to search for them in shady 

 pools or on the shady side of them." Whilst not 

 disputing the accuracy of this statement as a record 

 of the writer's own experience, I think it certainly is 

 not correct in all cases, nor should it be accepted as 

 a reliable guide in collecting. In the district worked 

 by myself, the neighbourhood of the port of Goole 

 and the rich tracts of marshland adjoining, charas 

 are commonly found in shady places. Chara vulgaris 

 is very common in deep shady ditches in Goole 

 Fields, and at Polleric Carrs near Doncaster. A 

 fortnight ago Nitella opaca was most abundant and 

 in perfect condition, with ripe fruit in several ditches 

 quite shaded by large hedges, and in Adlingfleet 

 drain, near Goole, it flourishes abundantly in like 

 circumstances, and also under the low arch of a 

 bridge. That "they appear to grow only in such 

 situations as are exposed to direct sunlight," is an 

 observation quite new to me, and the species named in 

 support of the assertion, " Tolypella intricata," does 

 not quite justify that, nor the following statement 

 that " in the summer they are in the best condition, 

 and their curious fruits are ripe." Tolypella intricata 

 is, according to my observations, developed very 

 early in the year, and is in the best condition with 

 ripe fruit in April, or early in May. After this time 

 it rapidly decays, falling to the bottom of the ditch 

 or pond. I have at present before me specimens, 

 now almost rotten, gathered from a locality where in 

 April they were strong and vigorous. Tolypella 

 glomerata is also in best condition early in the year ; 

 it occurred abundantly last year here, and was at its 

 best in April ; after June it was not to be found. In 

 keeping living specimens, my experience differs from 

 that of Mr. Saunders. T. intricata in a glass jar soon 



