1 62 General Notes. [February, 



in burning with flame and in its composition. Another jelly-like 

 substance from a Swiss peat bog, differing both from Dopplerite 

 and from the Scranton mineral has been described by Diecke. 



It is now proposed to group all these jelly-like minerals, pro- 

 duced by the decomposition of vegetable matter, under the one 

 generic name of Phytocollite {<por6v, xoila = " plant-jelly ") of 

 ie three minerals now known would be varieties. 



Special interest is attached to these substances, in that they 

 illustrate the first step in the transformation of peat into coal. 



Cossyrite. — Forstner 1 has given this name to a hornblendic 

 mineral which abounds in the igneous rocks of the Lipari islands. 

 It occurs in triclinic crystals closely approaching monoclinic 

 forms. It has an easy cleavage in two directions, the included 

 angle being 65 51'. Spec. grav. 3.75. It has the following 



SiO» Fe'O 3 APO 3 FeO MnO CuO CaO MgO Na»C> K 2 



43-55 7-97 4-96 32-87 1-98 .39 2.01 .86 5.29 .33 



Before the blowpipe it melts readily to a brownish-black glassy 



slag. It is partially decomposed by acids. It appears to be a 



variety of iron amphibole. 



Alaskaite.— A new sulphide of bismuth and lead from Alaska 

 mine, Colorado, has been described by Dr. G. A. Konig. 2 It 

 occurs as a pale lead-gray mineral of scaly structure and metallic 

 lustre, which forms a more or less intimate mixture with quartz, 

 barite, chalcopyrite, etc. It is soft, and has a spec. grav. of 6.878. 

 In the closed tube it decrepitates and fuses. On charcoal gives 

 characteristic coatings. It is soluble in sulphuric acid. It has 

 the following composition : 



Bi Vb Ag Cu Fe Zn S Ba 



51.35 17.51 3. 5.38 1.43 .20 17.85 2.83 



The formula given is (Pb, Zn, Ag 2 , Cu 2 ) S 4- (Bi Sb) 2 S 3 . 



Pseudomorphs of Copper after Aragonite. — Domeyko has 

 described some interesting cases of pseudomorphism of copper 

 after aragonite observed in some Bolivian mines. He found 

 hemitropic crystals of aragonite presenting all degrees of trans- 

 formation into metallic copper, and showing every transition from 

 crystals of pure aragonite to those of pure copper. 



Jacques and Cu . that by the 



,"93. Comp. Rend., i88r. 



