964 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



or two of growing moss or fungus was tten placed in the cell, having 

 first been carefully examined under the Microscope to see that it also 

 was free from Acarina and ova, and the cell was then ready for use. 

 One or two specimens of the larva, nymph, or species to be observed, 

 were placed in the cells ; the cover was put on and fixed with the clip. 

 By carefully attending to the hygrometric condition of the cell, 

 damping the blotting-paper or removing the cover to give air as 

 required, the animals throve well and got quite accustomed to the 

 cells. When it was desired to observe the inmates, which was done 

 at frequent intervals, the clip was removed and the cell transferred to 

 the stage. If low powers were sufficient, the cover did not require to 

 be removed if kept clean and if free from condensed moisture; if, 

 however, higher powers were used it was found that usually the cover 

 could be safely removed. 



Mr. Michael found these simple cells answer better than any of 

 the more elaborate apparatus. In particular he tried Mr. Macintyre's 

 ingenious cork cells, but did not find them answer for Oribatidse. In 

 the first place, many species, being wood-borers, simply ate their way 

 out or into the cork ; in the next place, the very minute ones got lost 

 in the interspaces of the cork and never reappeared ; in the third 

 place, the cells got dry too easily, and were apt to be too wet or too 

 dry ; the former of which was injurious, and the latter always fatal. 



Stokes's Spark Apparatus. — Mr. A. W. Stokes has shown at the 



Fig. 160. 



conversazioni of this Society and of the Quekett Club the sparks of 

 various metals under the Microscope, an exhibition which has proved 



