June, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



135 



tective reasons — with particles of dirt, which entirely 

 alter their appearance, and are by no means easy to 

 remove completely, and these grotesque moving particles 

 of dust and lUbris have to undergo very rigorous ablutions 

 before they are ready for the cabinet. 



Roya-l Microscopical Society. 



April 20. — Dr. Hy. Woodward, F.K.S., Vice-President, in 

 the chair. A large tank microscope, ni.ide by Thomas Ross, 

 presented to the Society by the Committee of the Qiiekctt 

 Microscopical Club, was exhibited. It was made not later 

 than the year 1S70, and was dcsisiied for the purpose of 

 examining objects contained in aquaria. It was a beautifully 

 made and highly-finished instrument, having nearly every 

 conceivable adjustment. The annual exhibition of Pond-Life 

 was given this evening by Fellows of the Society, assisted by 

 members of the Onekctt Microscopical Club. 



Quekett Microscopical Club. 



The 4ijth ordiu.ary meeting of the Club was held on 

 April 15, at 20. Hanover Square, W. — the President, Dr. K. J. 

 Spitta, V.P.R..-\.S., in the chair. A paper was read by Mr. W. 

 Wesehe, F.K.M.S., " On some new Sense-organs in the Diptera." 

 The paper was well illustrated by diagrams and drawings. 

 After briefly reviewing the investigations of Packard, Flatten, 

 Forel, Lubbock, and others into the senses of taste, smell, and 

 hearing in insects, the author proceeded to show that he had 

 found processes homologous with the " taste-hairs " of Krae- 

 peUn in some Orthoptcra, Coleoptera, Diptera. and Hymenop- 

 tera. Organs were then figined on the antenna; of Gastro- 

 philusctjui, L., Stratiomys chamckoii . L., and Bihio hoiinlnniis. L., 

 which were thought to be typical olfactory organs. Both the 

 antenn<E and palpi of insects were considered capable of re- 

 ceiving the stimulus of several senses, but their capacities 

 differed so much in various genera and species that a general 

 rule could not be formulated. The author had found new sense 

 organs on the femora of maTiy Diptera which he was unable to 

 assign to any sense of which we have conception. Other 

 organs of quite different construction had been found on the 

 libias of some minute Fmpid;e. Their functions were quite 

 unknown, and several experiments which had been made with 

 a ^ew of discovering the functions had yielded only negative 

 results. 



Journal of the Quekett Club. 



The April number of this Journal, wliich has just reached 

 me, contains sever.al useful articles and notes, amongst which 

 are a note by Mr. F. J. Cheshire concerning Abbe's test for 

 aplanatism, and a simple apertometer derived therefrom, the 

 apertometer being figured on a separate plate, so that it can be 

 cut out and used on the microscope in the way described by 

 the author. Mr. F. P. Smith, the new Editor of the Journal, 

 contributes a note on the spiders of the subfamily Erigoninse; 

 Mr. Rheinberg a note on an overlooked point concerning the 

 resolving power of the microscope ; and Mr. Scourfield con- 

 cludes his synopsis of the British fresh-water Entomostraca, 

 including the Ostracoda, Phyllopoda, and Brancliiura. 



Microscopic Slides. 



In the advertisement columns of this magazine will be 

 found a notice relating to the sale of duplicates of slides from 

 the collection of Mr. J. Hornell, of Jersey. Many of my 

 readers will be familiar with these beautiful preparations, 

 which include botanical as well as zoological subjects, and as 

 they are now being dispersed, and are offered at quite nominal 

 prices, I have felt myself justified in calling attention to 

 them. 



Practical Botany and Geology Classes. 



I have been much interested in receiving from Mr. J. M. li- 

 Taylor, Curator of the Free Museum at Paisley, particulars of 

 field rambles held in that neighbourhood from .'\pril till the 

 close of the public schools in July, with a view to giving 

 students a practical acquaintance with nature. The plan is 

 excellent, and well worth being taken up by other of our many 

 Free Libraries. Excursions are held twice 1 week, namely 



on Wednesdays and Fridays, leaving Paisley at 5.40 p.m., or 

 such other time as may be agreed upon, many of the excur- 

 sions being in brakes so as to get well into the surrounding 

 country. For the last five or six years during each session the 

 class has brought in from its field rambles the typical wild 

 plants, grasses, ferns, &c., of the time and district, and these 

 have been placed on view in the Free Museum with their 

 English ancl scientific names attached. Fresh specimens of 

 plants were added twice weekly, and lists thereof published in 

 one of the local daily papers. Nature knowledge was studied 

 practically at these excursions with the help of the camera, a 

 portable microscope, and a dredge for streams and ponds. At 

 the New Year a four days' exhibition was also held. By the 

 kindness of a local lady, Mrs. Poison, of Lcven Castle, prizes 

 of microscopes were offered to the members of the class for 

 the best collection of dried, mounted, and named wild plants, 

 grasses, and ferns ; aiul a microscope was likewise offered to 

 working men and women who would also make a dried collec- 

 tion, with names (which were obtained from specimens shown 

 in the Museum), but who were not members of any class or 

 Natural History Society, where names of plants were given. 

 This prize was gained by an ex-mason. For members of the 

 class each collection had to contain 400 specimens; and for 

 the collection made by working men and women there must 

 be 200 specimens. It is to be hoped that so excellent a scheme 

 mav find manv imitators. 



Notes and Qvieries. 



Chrysanthemum Fungu8. (C.H.C.) 



I have submitted the chrysanthemum leaves to Miss 

 E. M. Gibson, who has for some time been investigating this 

 fungus in tlie Cambridge i;niv('rsity Botanical Laboratories. 

 I learn from her that it is quite a new species, having only 

 been discovered some six or seven years ago, and has been 

 described, as far as present knowledge allows, by Dr. Ernst 

 Jacky, in the Zcitschrift f. Pflaur.cii-Krankhcitin, Vol. X. (ujoo). 

 It has been tentatively named " Uredo-chrysanthemi," but 

 though Mr. Massee, in the Gardener' a Chronicle speaks of other 

 stages teleuto or aecidio spores have not hitherto been 

 definitely found, or at least the evidence is not complete. 

 Miss Gibson says she has herself quite failed to find any other 

 stage than the nrcdo spores, as on the leaf you sent me. 

 Apparently the fungus, though unquestionably injurious, is not 

 necessarily destructive to the plants, but various species living 

 under similar conditions, show a curious variation in suscepti- 

 bility to attack, especially under high cultivation. .So far the 

 conditions favourable or otherwise to the fungus have also 

 not been determined. 



Making Rock Sections. 



Mr. C. H. Caffyn, of Hornsey, writes with regard to rock 

 sections: " I tried to make sections, as recommended in the 

 text-books, with emery powder on a piece of zinc or glass, but 

 it was a very long jol), and the results wore not altogether satis- 

 factory, and were quite out of proportion to the time employed. 

 I then thought it could perhaps be done with ordinary emery 

 cloth, and I find this does very well, and takes much less time. 

 I first chip off .as thin a flake as possible, and grind one side 

 flat on ' F ' emery cloth. Then I use No. i and then No. o, 

 and then polish on a piece of No. o that has been rubbed 

 down with a bit of itself to take the surface off. The piece of 

 rock is then stuck on a bit of plate glass with ordinary mucil- 

 age—I use Stephen's gum. When dry, the rock can be rubbed 

 down as mentioned above. Great care must be taken when 

 rubbing on the No. o to finish, as the section is apt to crumble 

 at the edges. When it is thin enough (which I generally judge 

 by reading print through it), put the piece of glass and section 

 in ordinary water till the section floats off the glass. Then 

 wash with a sable brush to remove all gum. Soak in methy- 

 lated spirit to remove water. Evaporate spirit, soak in ben- 

 zene, and mount in balsam and benzole." Mr. Caffyn has 

 sent me some slides to look at which have been made in this 

 way, and which seem quite equal to those made by the 

 ordinary process. 



[Communicationi and ciKiuiyies on Microuopical mailers are invileU, 

 ami should he addressed la F. SliillhigUm Scales, ■■ Jersey," SI. 

 Barnabas Road, Cambridge. \ 



