Notice of Ehrenberg's Memoir on Microscopic Life. 303 



the greater number appear to agree with European forms. He 

 then continues, thus — 



" Besides these fossils, which occur directly under the surface of a 

 peat-bog, and which consequently 'belong most probably to recent spe- 

 cies, I have also had an opportunity to examine a great number of not 

 only recent but still living forms from West Point. Prof. Bailey sent 

 me in the year 1842 some phials full of turf- water from West Point, 

 containing many living species of Bacillaria. These were filled with 

 water at West Point on the 2d of April, 1842, and on the 16th of June 

 I was able to show many of them in a living state at Berlin. I have 

 endeavored to compare all these living or decidedly recent American 

 species with the European, and have consequently drawn figures of all 

 of them. At the same time Prof. Bailey sent me a printed memoir, in 

 which he describes some of the fossil infusoria of Virginia, and a con- 

 siderable number of recent species from various places in the United 

 States, and particularly from West Point. The following is a list of 

 the species found at West Point, which Prof. Bailey has observed and 

 figured in Parts I and II of his memoir on American Bacillaria."* 



As this list furnishes the authentic names of the species figur- 

 ed in this memoir, we give it entire, believing that it will be 

 valuable for reference. 



I. Desmidiacea. (See Part I of Bailey's Bacillaria.) -• 



Fig. 1. Desmidium Swartzii ? = Desmidium Swartzii. 



= " tridens. 



= Pentasterias radiata ? 

 — Euastrum margaritiferum. 

 z= Desmidium aculeatum. 

 = Xanthidium fasciculatum. 

 = Arthrodesmus convergens. 

 = " quadricaudatus, p. 



rr: Xanthidium bisenarium. 

 = Desmidium glabrum. 

 = *Xanthidium arctiscon. 

 = * " coronatum. 



17. Arthrodesmus quadricaudatus,= Arthrodesmus quadricaudatus. 



18. " acutus, = " acutus. 



19. Micrasterias Tetras, =: Micrasterias Tetras. 



* This list includes only the species mentioned in Parts I and II of Bailey's Amer- 

 ican Bacillaria. Part III, including the Echinellse, and various Spongiolites, Phy- 

 tolitharia, and Dictyochae, had not reached Ehrenberg when this list was made out. 



