HARDWICKE'S SCIENCE-GOSSIP, 



Zeiss instrument the microscope may be at any chosen 

 angle, and this is where its greatest advantage hes. 

 In working, I use a small drawing-board, made so 

 that it can be arranged at any angle. Setting the 

 microscope with the tube at about 45°, I place the 

 drawing-board on the right hand side, level with and 

 on the same plane as the microscope stage, and the 

 paper placed directly under the centre line of the 

 mirror attached to the camera. The following points 

 should be attended to : (i) The angle of the drawing- 

 board should be exactly the same as that of the 

 microscope stage, and the centre of the drawing 

 should be under the centre line of the camera mirror, 

 otherwise there will be distortions in the drawings, as 

 Mr. Simmons found, and the picture will be out of 

 proportion. (2) The drawing should be on a level 

 with the microscope stage, that is, the distance 

 between the camera mirror and- the drawing paper 

 should be the same as between- the eye-piece of the 

 stage, if the magnification is required to be the same 

 in drawing as under the microscope. (3) The light on 

 the object and that on the drawing-paper should, in 

 neither case, be so bright or so dull that one obcures 

 the other, or either the paper will be too dark and 

 the pencil point lost, or in the other case, the paper 

 will be so illuminated that the object will disappear 

 altogether. A little practice will, however, soon 

 enable the respective lights to be arrived at easily ; 

 that upon the stage being modified in the usual way 

 from the lamp, and that upon the paper by means of 

 the neutral tint glasses supplied with the camera 

 lucida. I have found that blackening the pencil 

 point enables its being more easily seen against the 

 white paper. — M. L. Syhes, Patricroft. 



Pocket-Lens. — Would some reader kindly tell 

 me how I can ascertain the magnifying power of a 

 single (pocket) lens ? When I place it upon an 

 object, I want to know how many times that object 

 is magnified ? — W. F. Kehey, Maldon. 



Mounting Cochineal Insects.— There is one 

 thing I should like to draw attention to, and that is 

 the mounting of sections (cochineal) so as to show 

 the little purple granules, ' containing the colouring 

 matter. I have tried nearly every kind of liquid, but 

 find that in every case the colour is extracted and 

 mingled with the fluid, thus ruining the specimens 

 at once. The' only thing I find I can use is turpentine, 

 which preserves them splendidly, but the puzzle is 

 what cement can be used to contain the turpentine ? 

 Perhaps some correspondents could give hints con- 

 cerning this, which I think would prove useful to 

 others as well as myself. — If. Durrani. 



Land and Freshwater Shells. — Will any 

 Conchological readers of Science-Gossip kindly 

 oblige with particulars of the distribution of the 

 MoUusca in the home counties? Is there any pub- 

 lished list obtainable?— C/5a;7t'j/'a««a//, Junr., East 

 Street, Haslemerc. 



ZOOLOGY. 



The "Proceedings" of the Liverpool Geological 

 Society contain the following addresses and papers : — 

 By the President, "On the Life of the English 

 Trias"; "Notes on the Geological Excursion to 

 Anglesey," by T. M. Reade ; "Glacial iVIoraines," 

 by L. Gumming ; "Note on a Liverpool Boulder," 

 by T. M. Reade ; " The Contorted Schists of Anglc- 

 sea," by Dr. C. Ricketts ; "Microscopical Examina- 

 tions of Two Glacial Boulders," by J. E. George ;. 

 " On a Recent Discovery of a new Bone Cave at 

 Deep Dale, near Buxton," by J. J. Fitzpatrick ; "An 

 Examination of a Few Anglesea Rocks," by P. 

 Holland and E. Dickson, &c. 



The ' ' Transactions of the Penzance Natural 

 History Society " include the following papers, besides 

 reports of excursions, &c. :— " The Presidential 

 Address" of the Right Hon. L. H. Courtenay ;. 

 ' ' The Flora of Guernsey compared with that of West 

 Cornwall," by E. D. Marquand ; "Foreign Plants- 

 in West Cornwall," by W. A. Glasson ; "Plants- 

 growing in Tresco Abbey Gardens," by A. H. 

 Teague (this collection of living plants on a small 

 island is one of the most w-onderful facts in horti- 

 culture) ; Mr. Teague also contributes a paper on 

 " Starch as a Vegetable Production." 



The first Part of the " South Eastern Naturalist "' 

 is published as the Journal of the Associated Natural 

 History Societies of the south-east of England. 

 Among the chief papers in this first and well-edited 

 number are the following : — " Life History of the 

 Giant Hogweed," by J. Reid ; "Beds between 

 Chalk and London Clay," by George Dowker ; 

 "Notes on the Great Pipe Fish," by G. Dowker;. 

 "Leaf Fungi of 1889 in the Neighbourhood of Dover," 

 by W. T. Haydon ; "The Otolithes of Fishes," by 

 Sydney Webb; "A Neolithic Find near Dover," 

 by W. T. Haydon, &c, 



Black-Necked Grebe. — A fine specimen of the 

 eared or black-necked grebe {P. Nigricollis) was shot 

 on the Ouse, near York, October 23rd, and brought 

 to me in the flesh. It has since been stuffed and set 

 up by Helstrip, bird and animal preserver of this city. 

 Messrs Clarke & Roebuck, in their 1881 edition of 

 the "Yorkshire Naturalists' Handbook," record this 

 species as having occurred in Yorkshire on eight, 

 occasions. The bird is now in my possession. — 

 William Hewett. 



A New British Worm.— The Rev. Hilderic 

 Friend, F.L.S., has recently discovered a new and 

 curious British worm, first described in 185 1 by Dr. 

 Grube from a single Siberian specimen under the name 

 of Lumbriais vudtispiniis. On account of its difference 



