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of Dan vers, on the farm of Dr. A. Nichols, and of others nearby. 

 When exposed to the air, these masses at first pasty, became dry 

 and of a grey color, burned slowly with no flame and little 

 smoke, and when the vegetable matter had been consumed, the 

 ash-residue was found to be a congeries of exquisitely beautiful 

 forms made of pure silica. At one time the substance was call- 

 ed Tnarl but the application of a little acid soon dissipated 

 that delusion, there being no effervescence to indicate the car- 

 bonate of lime, on the presence of which in marl, much of its 

 fertilizing properties depend. 



The microscopes, then employed by Messrs. Cole, and Rus- 

 sell, though bringing out the beauty of these minute forms, yet 

 were inadequate to develope all their elegance and character. 

 Since that time improvements in the microscope have induced 

 many observers to attend to the examination of these tiny forms 

 of organized bodies ; and not only have vast beds of these depos- 

 its been found under peat bogs, but on the bottom of ponds, 

 where the substance is of a chalky whiteness and free from other 

 vegetable materials, and also in deposits of geological series, in- 

 dicating the previous action of marine growths at periods long 

 distant, as well as at periods comparatively more recent and 

 modern. 



These forms of aggregated individual organisms, have been 

 claimed by the zoologist and by the botanist as being both 

 animal and vegetable. The importance of their existence, 

 though thus minute, is seen in the part they play in formation 

 of soil, masses of this silicious earth being found of many in- 

 ches and even feet in depth, and extending over vast areas of 

 country. Portions of the specimen, presented by Prof. Rogers, 

 had been examined by the Institute's Microscopist, H. F. King, 

 and found to be rich in many highly interesting and character- 

 istic forms. The infusorial earths, Mr, R, suggested, were 

 valuable additions to a collection of Natural History, and should 

 be sought for and collected, if possible, abroad by our active and 

 enterprising members, who visit other regions of the globe. 



Geo. D. Phippen exhibited some twigs of a cherry tree in 

 his garden, at Bridge street, of extraordinary length and vigor, 

 being five or six feet long, which he said were instances of the 



