252 



SCIENCE-GOSSIP. 



and the two sides drawn together. The turpentine 

 group I put into a cell on crimson paper with a 

 removable cover, and at this moment of writing, 

 three months after the eggs were deposited by the 

 moth, they look as though quite recently laid, 

 making a beautiful top-light object for the 2-in. 

 binocular. The untouched batch I have still in the 

 original pill-box. They appear to be absolutely 

 unaltered, and apparently as fit to mount as the 

 group which I have mounted. We must not lose 

 sight of the fact that the ova I write of were un- 

 fertilised, a fact that would of course, to some 

 extent, bear on their subsequent conduct. Any 

 information hereon from the experience of others 

 would be useful to myself atd other readers. — 

 F. R. BroltensMre, Exeter. 



Artificial Dendrites. — In answer to Mr. 

 Abbott's question as to the classification of the 

 dendrites (ante. p. 191) — I presume he means the 

 South Kensington specimens — my knowledge of 

 the subject does not extend so far as to question 

 the classification there given. The theory broached 

 in your September number is not my own, but was 

 advanced by a gentleman before the Geological 

 Society in London about Januan r , 1899, and was 

 reported in your contemporary, "Nature/' As I 

 have not now access to the back numbers, I regret 

 that I cannot give the gentleman's name. When 

 I commenced the suggested experiments I had no 

 idea of publication. As to fluidity versus plasticity, 

 the difference is more of degree than of kind. I 

 found in my experiments that the more w-ater was 

 added, the finer and more numerous were the 

 ramifications, but that the difficulty of getting a 

 clear figure increased. I agree with Mr. Abbott as 

 to the difference to the eye between the South 

 Kensington specimens, but I fail to see the 

 difference to the mind, because in every experi- 

 ment there will be a variation of figure, according 

 to the fluidity, the speed in separating the planes, 

 the amount of pressure on them, etc. Probably 

 still greater variations would occur by using sub- 

 stances of different consistencies. — Edward Moor, 

 40 Arbitration Street, Doncaster. 



C. Baker's Slide Lending System. — Mr. 

 Charles Baker has sent us a further selection of 

 the notes accompanying the slides in his Slide 

 Lending Department. These include an introduc- 

 tion to the study of the Foraminifera, and descrip- 

 tions of the first set of twenty foraminiferal slides, 

 written by Mr. A. Earland, to which are added 

 half a dozen plates of excellent explanatory dia- 

 grams and illustrations ; descriptions of dissections 

 of an earwig, a cockroach, and a grasshopjjer, con- 

 tributed by Mr. F. P. Smith, whose name is well 

 known to readers of this magazine ; and descrip- 

 tions of a set of twenty slides dealing with pond 

 life, mainly rotifers, for which Mr. C. F. Rousselet 

 is responsible. This last is exceptionally interest- 

 ing, and we should have liked to have made 

 extracts therefrom had space permitted. Mr. 

 Baker's scheme deserves success; as we have 

 already said, the mere looking at slides is of no 

 advantage. It is their study that is essential, and 

 no one can fail to benefit by, as well as be interested 

 in, slides accompanied as these are, by interesting 

 explanations, which in many cases cannot fail to 

 tempt the observer to make further observations 

 for himself — a consummation most devoutly to be 

 wished. The subscription to this series is so low, 

 in comparison with its value, that we can recom- 

 mend it to our readers. 



Mounting Web of Spider. — I have to thank 

 Mr. Payne for his note hereon (ante, p. 211) ; but as 

 he says nothing about the viscid globules on the 

 concentric strands which formed the principal 

 feature in the beautiful slide I remember seeing 

 in a friend's collection some long time since, I 

 fear, in his preparation, these had no place, had 

 evaporated, or become absorbed by the strands. I 

 have now a dried portion of a garden-spider's snare 

 beautifully displayed on a slip, and taken with the 

 view of mounting ; but the globules are gone, the 

 feature I wish to preserve. — F. II. BroJtensJiire, 

 Exeter. 



MEETINGS OF MICROSCOPICAL SOCIETIES 



Royal Microscopical Society. — 20 Hanover 

 Square. January 15th, 8 p.m. 



Quekett Microscopical Club. — 20 Hanover 

 Square, January 3rd, 7 p.m. : January 17th, S p.m. 



Manchester Microscopical Society. — Grand 

 Hotel. Manchester, January 9th, 7 p.m., "The 

 microscopic structure of limestone," illustrated 

 with lantern slides and by a microscopical demon- 

 stration ; January 30th, 7 p.m., Annual Meeting, 

 Report of the Council, Election of Officers. 



Sunderland Microscopical Society. — Sub- 

 scription Library. Sunderland. January 21>t. 

 7.30 p.m. 



ANSWERS TO CORRESPONDENTS. 



E. G. W. (Alnwick).— Mr. Cole, the well-known 

 mounter, recommends the following procedure 

 with regard to the cutting of sections of whole 

 insects and staining them: — "Embed in paraffin 

 or celloidin, make sections, and stain afterwards. 

 The latter embedment would answer better. I do 

 not think it would be possible to stain wdiole 

 insects in bulk ; the staining solution would not 

 penetrate the chitine." Concise and reliable 

 instructions for embedding in celloidin will be 

 found in Cross & Cole's " Modern Microscopy." 

 pp. 121, 125 ; in Carpenter's "Microscope " (8th ed.), 

 pp. 503-50U ; or in Lee"s " Microtomist's Yade- 

 Mecum" (5th ed.), pp. 120-131. If you have not 

 access to any of these works I shall be glad to give 

 you full information as to the procedure. 



[For further articles in this number on Micro- 

 scopical subjects, see pp. 230, 231, 23L and 215.] 



EXTRACTS FROM POSTAL MICROSCOPICAL 

 SOCIETY'S NOTEBOOKS. 



(Continued from page 212.) 



[Beyond necessary editorial revision these ex- 

 tracts are printed as written by the various 

 members. — Ed. Microscopy, S.-G.] 



Fossil Stents of Crinoids. — Fig. 10 represents 

 fossil crinoids from the same beds of Wenlock 

 shales. These interesting inhabitants of Silurian 

 Carboniferous seas are too well known to need 

 description. 



Spicules of Gorgonia. — Figs. 11 and 12 represent 

 species of Gorgoniadae mounted by the Rev. .1. E. 

 Vize, F.R.M.S., and presented by him to mc some 

 time ago. They deserve careful examination. 

 Fig. 11, Donatio, lynenrittm ; Fig. 12, Lopliogorgia 

 palina and Paragorgia arhorea. 



A n lit trt dia and Globules of Chara fragilis. — 

 The sexual reproductive organs of the Characeae, 



