1899] 



MICROSCOPICAL JOURNAL. 



97 



all segmentated, the latter most rapidly. After three 

 days, it had become a typical gastrula, the nucleated frag- 

 ment a smaller gastrula, and j the non-nucleated also a 

 gastrula. All the cells showed nuclei. 



Indian Corundum. — In India, it is found in connection 

 with basic and acid rocks. Particularly a felspar rock in 

 the Coimbatore district of Madras yields unaltered corun- 

 dum which shows no evidence ©f secondary origin. Cor- 

 undum may be crystallized out from certain slags which 

 contain an excess of alumina. 



A Lantern Microscope. — Hugo Schroeder gave a lecture 

 and demonstration of his Electric -Microscope in London 

 Jan. 11, 1899. It is capable of a magnification of 10,000 

 dia. Its efficacy is due to a new lamp of semi-jncandes- 

 cent type. 



