410 Miscellanies. 



this action. Such is not a correct statement ; by exposure to atmos- 

 pheric vapor, strong solutions of muriate of tin become weaker, and 

 any masses of undissolved tin, projecting into the weaker solutiony 

 "will decompose the denser solution below. In numerous trials, I 

 have found all tlie cases of precipitation referable to different states 

 of two solutions resting in contact, 

 Roxbury Laboratory, March 16, 1840. 



22. JVezo Minerals. — Associated with the nitrate of soda of the province of Tara- 

 puca, I have found the iodate of soda or potash, in irregular crystalline grains. 

 Tlie chloriodate of magnesia, in the state of solution, colors parts of the masses of 

 the nitrate of soda a lemon yellow color. This new salt, doubtless, exists in mine- 

 ral waters, conferring its highly active properties on them. The so called sulphate 

 of alumina, from near Iquque, is a new mineral species, composed essentially of 

 sulphuric and phosphoric acids, alumina and magnesia. It is entirely soluble in a 

 small proportion of water, and is one of the most beautiful of saline minerals. 

 Borate of magnesia, containing a larger than usual proportion of water under a 

 different crystalline form, is found in the vicinity of the latter. A. A. Hayes. 



March 16, 1840. 



23. Jin additional fact illustrating the hiferior surface of the Calymene Bvfo ; 

 by Prof Jacob Green, M. D. — In one of the recent numbers of your valuable 

 Journal, there were published a few facts, which I had been so fortunate as to col- 

 lect respecting the structure of the inferior surface of the trilobite. The Calymene 

 Bufo was the species to which most of my remarks applied. The following addi- 

 tional note will perhaps be interesting to some of your readers. 



Within a few daj's I received from my friend, Mr. T. A. Conrad, the zealous 

 and distinguished fossilist of the New York survey, thi"ee highly interesting frag- 

 ments of the C. Bufo, which develop a small portion of its anatomical structure 

 not heretofore observed. In my former communication above noticed, the follow- 

 ing statement will be found. " None of our fragments exhibit fairty the small 

 surface on each side of the gullar plate, and the edge of the buckler beneath the 

 eyes. This space was probably concave," &c. Now the fragments of Mr. Conrad 

 illustrate this part of the organization in quite a satisfactory manner. This space 

 is concave, and the edge of the buckler beneath the eyes, which in one of the 

 specimens is very perfect, is marked by six denticulations or tooth-like prominen- 

 ces along the inferior edge of the lower lip. The lower lip has therefore a smooth 

 or unbroken edge in front, and is terminated on each side below the eyes by a 

 denticulated margin. 



In no instance have I seen the interior edge of the buckler so perfect as in one- 

 of the above specimens, and in looking at the groove which forms the lips, one is 

 almost persuaded to believe that the mouth of the animal was really located in 

 this part of the head. 



