156 



SCIENCE-GOSSIP. 



CONDUCTED BY F. SHIl.I.INGTON SCALES, I-. R.M.S. 



The Richmond Park Ponds. — I am glad to see 

 attention drawn to these ponds and pools, as, person- 

 ally, I have found them especially productive in one. 

 branch of Pond Life, Freshwater Algae. To mention 

 tile algae to be found here, would be to enumerate the 

 chief forms of these plants. They occur in the Pen 

 ponds and smaller ponds and pools: — Chara, Niiella, 

 Cohochaetc, Aphanochaete, Chae.tophora (several 

 species), Draparnaldia, Sfigeoiioiiiitiii (several 

 species), Hormisna, Ocdogonhiin, Bidbochoele, Clado- 

 phoTa, Microspora^ Eiitijroinoipha, Vattcheria^ Spiro- 

 gyra (several species), Zygneiiia, JMesocarpus 

 Paiidoj'ina, Volvox (both ^/t^/Jtz/.?;- and w?;z(7;- with ripe 

 oospores on one occasion), Pediastriiiii, Apiocyslis 

 Bohyococciis, Mischocpccus, Scenedesiims, Nephrocy- 

 tiitin^ Gloeocystis^ Phiirococcits^RivuIaria^ Tolypothvix. 

 Aiiahana, Oscillaria, Cosnmriiiiii, Closfeiiu/ii. As 

 regards other forms of .Pond Life, I have met with 

 Hydra of a dull brown colour, and also of a rich 

 orange-buff. That peculiar condition of Eiiglena, 

 during which the individuals are aggregated together 

 and are invested with cellulose cell-walls through 

 which they break away, sometimes forms a thick grey- 

 green scum on the surface of the Pen ponds. From 

 what I have seen when collecting Algae, it would 

 appear that the ponds and pools of Richmond Park 

 would well repa\' systematic investigation in all 

 branches of Pond Life. In conclusion, it will be of 

 interest to mention, that in the neighbourhood occur 

 two such interesting Algae as Batrachospernnim and 

 Chantransia. — C. E. Britlon^ 35, Diigdale Street, 

 Ca/ul)erweU^ S.E. 



MANCHESTEli MtCROSCOPICAL SOCIETY. — We 



have received from the Manchester Microscopical 

 Society their Annual Report and Transactions for the 

 year 1S9S, and heartily congratulate the members not 

 only on their numerical and financial position, but on 

 the good and practical work that their Society is 

 evidently doing. The transactions themselves are 

 interesting reading, even to non-members of the 

 Society, and most of the papers are well illustrated 

 with excellent plates. We may mention specifically 

 papers by Mr. A. T. Gillanders on " .Scale Insects,'' 

 by Mr. W. PI. Pepworth on " Myxomycetes," by 

 Mr. W. Moss on "The Genitalia of the British 

 /Pya/i/u'a," by Mr. Chas. Bailey on " Maize,"' by 

 Mr. Frank Paulden on " Peripatus leiiikarfi" an 

 Australasian form, and liy Mr. Wm. Blackburn on 

 " Myriolhcia phrygia." The annual address by the 

 President, Prof. Weiss, of Owen's College, is also 

 printed in full, the subject being "Life.'' Besides 

 the usual field-work the Society has a sub-section for 

 practical work in mounting and technique. It 

 possesses a library, instruments, and a cabinet of micro 

 and lantern slides. The Society has recently 

 extended its usefulness by organizing lectures with 

 demonstrations for the benefit of outside societies and 

 institution.s. Eighteen such lectures have been given 

 in the Manchester district during the past twelve 

 months and we are not surprised to learn that the 

 scheme has been eminently successful. The report 

 and transactions can be obtained from the lion. 



Secretary, Mr. E. C. Stump, 16, Herbert Street 

 Moss Side, Manchester, post free for one shilling and 

 eightpence. We commend it to the notice of other 

 societies engaged in similar work. 



New I'aiN. Immersion Objective. — Messrs. R. 

 and J. Beck have sent for our inspection a new ,Vin. 

 imtnersion objective with a numerical aperture of 1.4 

 and an aplanatic cone of 1.35 N.A. It is perfectly 

 achromatic, and the makers modestly and rightly 

 claim no more than this, but we can speak highly of 

 the performance of the lens. It is exceptionally free 

 from colour, the definition is excellent, and the 

 increased quantity of light passed is most noticeable. 

 It bears comparatively high eye-piecing \vell. The 

 working distance is of course rather less than in 

 objectives of lower aperture. The price brings it 

 within the reach of all workers requiring an objective 

 of this description, being ^S, or £^ io.s. with correc- 

 tion collar. 



New Immersion Condenser. — Competition 

 between the opticians grows apace and the worker and 

 the amateur benefit accordingly. Messrs. Beck have 

 brought out a new immersion condenser, w'hich we 

 illustrate herewith, with a numerical aperture of 1.36 

 to 1.4, and an aplanatic cone of 1.3 N.A. The com- 

 bination consists .of four systems of lenses, the front 

 of which is a hemisphere with three combinations 

 behind, and constructed on the principle of an oil- 

 immersion objective. By the courtesy of the makers 



rc 



we have had an opportunity of testing this condenser 

 in connection with the objective 1.4 N.A. above 

 described and are much pleased with its perform- 

 ance. The working distance is o.6in. By an 

 ingenious arrangement the optical part of the 

 condenser can be reversed in the mount so that it 

 may be used with microscopes fitted with under-stage 

 fitments instead of the usual focussing substage. The 

 top lens is also removable. The price of the optical 

 part is only £,z 15s. ; of the mount, with iris 

 diaphragm and carrier for stop, £1 : the stops and 

 coloured glasses in brass box, I2s. Total, ^4 7s. 



New Catalogues. — We have received catalogues 

 of microscopes and apparatus from Mr. J. H. 

 Steward, of 406 and 407, Strand, and 7, Gracechurch 

 Street, and from Messrs. A. Clarkson & Co., of 

 Ilolborn Circus. The former contains several micro- 

 scopes of excellent design, aiid a full list of accessories, 

 but is cumbered, as is too often the case, with types 

 of microscopes of antiquated patterns long since 

 superseded, which, we think, would be better deleted, 

 as they do not enhance the reputation of the maker, 

 and are likely to mislead beginners. Messrs. 

 Clarkson's catalogue is almo.st entirely devoted to 

 second-hand instruments, all offered at moderate 

 prices, and nearh' all are of good and recent models. 



