KNOWLEDGE & SCIENTIFIC NEWS. 



FAuGusT, 1906. 



Conducted by F. Shillington Scales, b.a., f.r.m.s. 



Royal Microscopical Society. 



June 20, Dr. Dukinfield H. Scott, K.R.S., IVcsident, 

 in the chair. Mr. J. T. Holder exhiljited and described 

 an old microscope made by .A^ndrew Pritohard in 1846, 

 which had been lent for exhibition by Mr. W. R. 

 Reeves, of Liverpool. Dr. Hebb exhibited some high- 

 power sterco-photo-micrographs of diatoms at magnifi- 

 cations of 500 to 2,000 diameters, received from Mr. 

 Dollman, of Adelaide, South .Australia. The President 

 read a paper on ''The Structure of .some Carboniferous 

 I'erns." He pointed out the change which had taken 

 place in the last three years in our conception of the 

 carboniferous ferns, so- many examples of fern-like 

 plants being now known to have borne seeds or being 

 suspected of having been seed-bearers, that compara- 

 tively few undoubted ferns were left, and it was 

 questioned whether, at least, in the Lower Carboniferous 

 true ferns existed. One family, the Botryopteridea;, 

 was admitted to be well represented in Lower as well 

 as L'pper Carboniferous times, and Mr. Newell Arbor 

 has proposed to establish a group of Primofilices to in- 

 clude this and other primitive ferns of the Palaeozoic 

 age. The object of the communication was to- give a 

 few illustrations of the ancient race of ferns. The 

 Botryopteridese were first described, beginning with 

 the type genus Botryopteris. The genus ZygopUris 

 was next considered, and a new genus from the Lower 

 Coal Measures of Lancashire, for which the name of 

 Boirychioxyton was proposed. Two or three other ex- 

 amples of the family having been noticed. Dr. Scott 

 described certain annulate fern sporangia. The germina- 

 tion of spores within a sporangium was demonstrated, 

 and this sporangium had quite recently been identified 

 as belonging to Siaiiropicris oldliamia. The paper was 

 illustrated by fossil and recent sections thrown on the 

 screen, and bv lantern slides. 



Quekett Microscopical Club. 



June 15. Mr. .\. E. Hilton read a paper ''On the 

 Study of the Mycetozoa." Having referred to the 

 still existing uncertainty as to the correct classification, 

 the lecturer dealt with the distribution and general 

 habitats of the group. Tlie life-cycle in brief is : The 

 spores, usually about 10 m in diameter, rupture when 

 immersed in water, and jelly-specks, each with a nucleus 

 and two or three vacuoles, are liberated. These are 

 the swarm-cells. They assume first an amoeboid form, 

 and subsequently resemble flagellate infusoria. After 

 multiplication by encvstment and division, they coalesce 

 into a larger mass, the plasmodium; this, after slowly 

 creeping about after food on decaving vegetable sub- 

 stanCies, ultimately comes to rest and throws up 

 sporangia, which vary from ^^^ to J of an inch in height. 

 The sporangia scatter spores and a new life-cvcle 

 begins. These various stages were described at length 

 with reference to a series of coloured drawings of 

 Comatricha obliisafa, one of the commoner forms. 

 Members yet undicided as to what line of^ research to 

 follow were strongly urged to take up the study of this 



group. Its simplicity, especially when compared with 

 botany or entomology, was pointed out, and books were 

 named, dealing with the subject, and hints on the collec- 

 tion and cultivation of specimens were given at length. 

 Mr. Hilton exhibited a large number of specimens of 

 Mycetozoa, under micro-scopes, and Mr. J. Burton 

 showed some active swarm-cells of Brejcldia maxima. 



New Object Finder. 



Messrs. R. and J. Beck, Ltd., have .sent me for in- 

 spection a new finder, by Mr. J. M. Coon, which was 

 recently exhibited at a meeting of the Royal 

 Micrtxscopical Society, and which is designed for use on 

 the ordinary plain stage of any microscope. There is 

 a special label for attachment to the microscope slip, 

 and a pointer with universal movements and clamps 

 for attachment tO' the microscope stage. This pointer 

 has two points, as illustrated herewith. The label will 

 be seen to be ruled in squares, numbered horizontally 

 and lettered vertically for convenience of reference, and 

 sub-divided into sixteen equal triangles for further re- 

 finement if necessary. In addition, two " focussmg 

 marks," or adjustment marks, are provided The label 

 being affixed to the right of a slide in the usual way, 

 the objective is focussed on the left-hand mark. The 

 pointer is clamped upon the stage, and so adjusted that 



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the main point lies upon the right-hand mark, and the 

 other point is on the straight line upon the end of which 

 this setting mark is situated. It is obvious that when 

 the slide is now moved bodily to the right so as to 

 bring the object itself into the field of view of the 

 microscope, the pointer (which has not been moved) 

 will, if an ordinary 3 by i inch slide is used, come to 

 point over some of the intersecting lines of the label. 

 These are noted, and either the letters and numbers are 

 taken, or two ink-spots are made as a register. To 

 find an object, it is therefore only necessary to repeat 

 the process and to again move the slide until the pointer 

 stands over the register marks. A microscopist can 

 thus not only register a slide for use even with high 

 powers, but can .send it to another observer with in- 

 structions that will enable him to examine any portions 

 so registered. The price of the finder, with labels, is 

 half-a-£ruinea. 



Stain for Photo-Micrography. 



.A note in the current issue of the Journal of the 

 Royal Microscopical Society, gives the following stain 

 as being recommended by Mr. E. Moffatt, for photo- 

 micrography : — Fuchsin, .06 grm.; methylen-blue, 

 .04 grm.; alcohol (90 per cent.), 5 c.cm. Add aqueous 

 solution of carbolic acid, 5 per cent, to make up to 25 

 c.cm. Make films from cultures, in the usual way, and 

 flood with the filtered stain; warm gently, wash well, 

 dry in air, and mount in balsam. This solution is a 

 very powerful stain, and used as above, gives excellent 

 results with diphtheria, anthrax, cocci, and other 



