1883.] 



MICROSCOPICAL JOURNAL. 



lO' 



importance, especially when working 

 on an exceedingly transparent object, 

 where the inner membranes could be 

 distinctly separated from those above 

 them ; or, in tracing out fine nerve 

 fibres, which, passing over or under 

 each other, could be resolved in a way 

 which was entirely impossible by any 

 other means. 



Mr. Beck believed they were only 

 as yet in the infancy of the binocular 

 microscope ; and he looked forward to 

 the time when much more attention 

 would be paid to its construction, and 

 particularly to the question of ascer- 

 taining the best point at which the 

 prism should be placed to get the full 

 field, without adventitious aid in the 

 way of illuminators, by which im- 

 proved results would, no doubt, be ob- 

 tained. He believed that the binoc- 

 ular was the microscope which would 

 be used in the future. 



Dr. Gibbes said he could corro- 

 borate all that had been said on the 

 subject of the binocular, and espe- 

 cially its value when used with a aVth- 

 inch in examining those very minute 

 parasites to which his attention had 

 been given, as it enabled him at once 

 to see whether they were outside or 

 inside the tissue. 



The " Facility " Nose-piece. 



We have already alluded to this 

 convenient and ingenious accessory in 

 these columns, and now we present 

 our readers with an illustration of it, 

 (fig. 19) which will give a good idea of 

 its merits. We have used one of these 



nose-pieces considerably, having it at- 

 tached to the stand all the time, and 

 have found it a very convenient acces- 

 sory. We prefer it to the double nose- 

 piece heretofore used on the same 

 stand, 



A small grooved ring is provided 

 for each objective, which is screwed 

 down against the shoulder. The ring 

 is seized by three jaws in- the nose- 

 piece which act upon the principle of 

 a self-centering chuck. By a very 

 short turn of the milled head the ob- 

 jective is securer or released. The 

 ingenious arrangement of the jaws 

 need not be described in detail, but in 

 practice they work beautifully. 



The rings on the objective are so 

 small that they do not interfere with 

 putting the latter into its box. 



Zool. Anzeiger VI., N. isg {8th Jan., 188^,.) 



1. Balbiaiii and the Conjugation 

 of the Infusoria. 



BY O. BiJTSCHLI OF HEIDELBERG. 



Although I am in no way a friend 

 of controversy in the province of our 

 science, knowing that it has no value 

 at all for its progress, I feel com- 

 pelled to lay aside for once this dis- 

 inclination, and to criticise a colleague, 

 with whom I least like to fall out in 

 this manner. I desire to be brief and 

 therefore begin at once with the special 

 subject of discussion. 



In the Journal de Micrographie, 

 little circulated in Germany, edited by 

 J. Pelletan, there have been published 

 since February, 1881, the lectures 

 delivered by Prof. Balbiani at the Col- 

 lege de France, on "Protozoa." From 

 the tone of these publications, it be- 

 comes apparent that they proceed di- 

 rectly from the pen of Balbiani, and 

 were not written down by a hearer of 

 his lectures. 



Until now these publications occu- 

 pied themselves with the description 

 of the Infusoria, and quite recently 

 there began also the discussion of 

 Sporozoa and Flagellata. What in- 

 terests us here is the description 



