ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 



219' 



of Petri dishes or objects mounted on extra large slides. The stage'is 

 mounted on a base plate, which allows of the object being revolved 

 concentrically in the field of view. 



(2) Eye-pieces and Objectives. 



Zeiss' Anastigmatic Magnifiers.* — Four lenses enter into the con- 

 struction of these anastigmatic magnifiers (tig. 27), which have both a 

 large field and large working distance. They are supplied in three- 

 different powers, 16, 20, and 27 diameters, either as single magnifiers in 



Fig. 27. 



a mount suitable for dissecting stands, in the form of folding pocket 

 lenses, or any two powers mounted in pairs, as shown in the illustration. 



^----^^^ 



Fig. 28. 



Zeiss' Verant Lenses.t — In these Verant lenses there is a virtual 

 stop about 2*5 cm. behind the nearest lens surface, a sharp and un- 



* Carl Zeiss' Special Catalogue, 1906, p. 6. 



t Tom. cit., p. 7. 



