174 Miscellanies. 



Admitting 0.1 1 atoms of magnesia, and 0.04 atoms of protox. iron, 

 to be in combination with alumina, and only accidental, and 0.16 of 

 water, to be mechanically lodged in the mineral, then it will be a bi- 

 hydrous tersilicate of magnesia ; and is therefore the magnesite of 

 Dr. Thomson's Mineralogy, Vol. I. p. 178. 



Another mineral was sent to Dr. Thomson, under the name of 

 Deweylite, by Dr. Holmes, concerning whose locality nothing is 

 recollected, and which consists of 



41.42 



10. Ornithichnites in Connecticut. — Extract of a letter from 

 Prof. E. Hitchcock, dated June 28th, 1836. — In my account of 

 the Ornithichnites in New Red Standstone, given in the last Jan- 

 uary number of the Journal, I intimated that perhaps they might 

 be found at a place called the Cove, in Wethersfield, Ct. I went 

 to Hartford last year mostly to visit this spot; but having been there 

 informed that no rocks existed at the Cove, I did not go there. Yet 

 recently a young gentleman of the Junior Class in Amherst Col- 

 lege, whose father resides near the spot, and who had carefully ex- 

 amined my specimens of Ornithichnites, informs me that he has dis- 

 covered them at the Cove in considerable abundance and variety. 

 But I will give you an account of them in his own words. 



" The first specimen I examined was a step stone which had been 

 in use nearly a century ; on which were four steps, whose length 

 was 14 or 15 inches, and the length of the foot 4 or 5 inches. The 

 middle toe has three tuberous swellings, the outer ones two. The 

 claws are all of considerable length. This resembles your O. tube- 

 rosus, a dubius. Upon another door step in the same vicinity, I 

 found two rows of tracks, the feet having the same direction. The 

 length of these steps is 29 inches, and of the foot 7 inches, swell- 

 ings and claws on the toes. 



At the Rocky Hill quarry, in Hartford, I found a specimen close- 

 ly resembling that just described : the length of the foot 6 or 7 

 inches, and of the step 27 inches — I found there but two tracks. 



