56 



SCIENCE-GOSSIP. 



CONDUCTED BY J. H. COOKE, F.L.S., F.G.S. 



To whom Notes, Articles and material relating to Microscopy, 

 and intended for Science-Gossip, are, in the first instance, 

 to be sent, addressed "J. H. Cooke, EdUstone, Battenhall 

 Road, Worcester." 



Notices and Reviews. — We shall be glad to 

 notice all books, papers, reports, bulletins, periodi- 

 cals, etc., within the scope of the "Microscopy" 

 section, which may be sent to us for that purpose. 



Microscopical Technique. — Professor G. C. 

 Huber, of the University of Michigan, is contri- 

 buting a series of useful articles on "Microscopical 

 Technique" to the columns of the "Journal of 

 Applied Microscopy." In the current number he 

 deals with " The Hardening of Tissues for Micro- 

 scopical Examination." 



The American Microscopical Society will 

 hold its next meeting on August 30th and 31st, and 

 September ist, 1898, at the University of Syracuse, 

 N.Y. It is expected that the Congress this year 

 will be largely reinforced by members of the 

 American Society for the Advancement of Science, 

 who are holding their meeting a few days before at 

 Boston. 



A Student's Microtome. — In selecting a 

 microtome, the main considerations with the 

 majority of students are cheapness, general appli- 

 cability, ease of manipulation, and durability. The 

 difficulty hitherto has been to find an instrument 

 that combines all of these desiderata. There are 

 plenty of microtomes on the market, but, as a rule, 

 the price is much above the average student's 

 means. To supply what was a manifest want, 

 Messrs. Reynolds and Branson, of Leeds, have 

 just introduced an instrument which combines all 

 of the above requisites, and which is so simple and 

 practical that it has been introduced into the 

 Leeds Medical School. We have had an oppor- 

 tunity of trying one of these instruments, and 

 while cordially recommending it, we have no 

 hesitation in saying that no better value has ever 

 been offered for the money. As will be seen from 



Reynolds and Bk.^nson's Stude.nt's Microtome. 



the illustration, the instrument is arranged to slide 

 on a glass plate with a circular roughened ring, 

 the substance to be cut being imbedded and fixed 

 on that plate. Sections of any degree of thickness 

 may then be cut by simply raising or lowering the 

 screw. The microtome is so arranged that any 

 razor may be clamped to it, and it will be found 

 extremely useful to students in physiology, 

 botany, etc. The price of the microtome, with 

 glass plate, is only 4s., and razors are supplied at 

 IS. and 2s. each. 



A Lobster's Ears. — The ears of a lobster are to 

 be found at the bases of its antennae, each of which 

 terminates in a cul de sac, or pouch. The external 

 covering of skin of these pouches is a continuation 

 of the body covering, though somewhat modified in 

 structure. In each pouch are always to be found 

 several minute grains of sand, and these grains of 

 sand play prominent roles in the drama of audition. 

 The microscope shows that the floors of the ear 

 pouches are papilomatous, or dotted thickly with 

 minute papules, or elevations, each surmounted by 



A--'. 



Ear of Lobster (modified from Farre). 

 A, Orifice ; b, auditory hairs and sandgrains. 



a hair. If one of these papules be examined, a 

 terminal nerve-tuft will be found ensheathed in its 

 thin walls ; a microscopic nerv'ule leads from it, 

 together with thousands of its fellows, to the 

 auditory nerve, which passes on into the sen- 

 sorium. This description of a lobster's ear. is 

 derived from a careful study, by Dr. J. Weir, of 

 fresh specimens. 



Circulation of Blood. — The standard method 

 of examining the circulation is that of extending 

 on a frog-plate the web between the toes of a 

 frog's foot. As, however, most amateur micro- 

 scopists find it difficult to obtain a frog when they 

 require one, it might be of advantage to some of 

 them to know that the tadpoles of the common 

 frog form excellent substitutes during their 

 embryonic state, and that in the thin expansion of 

 the tail the circulation is exhibited to perfection. 

 These tadpoles are easily obtained in almost any 

 district, and may be kept in a small aquarium or 

 fish globe, where they will be handy when required. 

 The method of examination is very simple. The 

 tadpole is caught and transferred to an ordinary 

 slide, and a lump of loose wet cotton-wool is placed 

 over it, holding it down fast to the slide, and 

 leaving the tail free for observation. If there is 

 any tendency to curl the tail up on to the object- 

 glass, an ordinary thin glass cover may be placed 

 over it to keep the tail steady. The tadpole can 

 be kept thus for an hour or more without any 

 apparent discomfort, provided that the cotton-wool 

 be kept moist. It might be mentioned that the 

 tadpoles are of very little use for this object after 

 the development of the legs, as the circulation then 

 ceases, and the tail becomes opaque I always use 

 a one-inch objective and dark ground illumination. 

 — Lewis H. T. Chave, Wevmouth. 



