266 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



a revolving annulus to tlie body. The revolving diaphragm plate is 

 recessed into the stage. When the largest aperture is used, the thread 

 in the stage will allow of a fitting being screwed into it to receive the 

 various stage ai)paratus. 



For class demonstration it is found that the hinged joint to the 

 limb is not essential, and it is therefore made in two forms, with and 

 without joint. 



Crouch's Portable Histological Microscope. — Mr. H. Crouch has 



Fio. 37. 



