APPENDIX. 109 



MISCELLANEOUS NOTES. 



BACILLARIA. Should this Volume meet the eye of 

 the naturalist, the omission of any notice of the nu- 

 merous family of Bacillaria, (the Stick-like Animal- 

 cules of Ehrenberg), some species of which are gene- 

 rally present in water containing Infusoria, will require 

 explanation. It has arisen from the opinion that not- 

 withstanding the observations of M. Ehrenberg, the 

 animal nature of these organisms is very doubtful. I 

 am more inclined, with the botanists, to refer them 

 to the vegetable kingdom, and consider them as Alga3, 

 belonging to the order Desmidiacece, than as being in 

 any way related to the Infusoria. 



MICROSCOPES. The microscope employed in the in- 

 vestigations described in the text, was an achromatic 

 made by Mr. Ross, the eminent optician, (Featherstone 



