246 Botanical Letters from J. J. Rousseau to M. Gouan. 



73. Smaragdite, grass-green, occurring in the same specimen as 



No. 67, but containing thin films of paratomous augite-spar, 3.129 



74. Basaltic Hornblende, fragments of imbedded crystals, from 

 Lower Stiria, 3.167 



75. Zoisite, grey, cleavable, from the Saualpe, 3.269 



76. Zoisite, rose-red, compact from the Radlgraben, Carinthia, 3.334 



77. Epidote, brown, thin columnar composition, 3.336 



78. Zoisite, ash-grey, cleavable, from Bayreuth, 3.355 



79. Pistazite, dark pistachio-greer. crystals from Arendal, 3.425 



80. Wollastonite , a brownish-white variety from the Bannat, 2.805 

 *81. Arfvedsonite, large, perfectly cleavable individuals, 3.431 



This mineral must be included in the genus augite-spar 

 of Mohs, to the species of which it is allied by a very high de- 

 gree of resemblance, particularly to the hemi-prismatic augite- 

 spar. Mr Brooke has found the angles of its prism of cleav- 

 age to be 123° 55', different from the angle of hornblende, 

 which he quotes at 124°30'; but even if the two substances 

 did agree in this respect, their specific gravity would render 

 it unavoidable to consider them as distinct species. 



82. Prismatic Azure-spar, the dark blue variety from Vorau, in 

 Stiria, 3.039 



83. Prismatoidal Azure-spar, pale-blue, crystalline fragments, 

 Stiria, 3.024 



"84. Elaolite, of a pale-brown colour, 2.589 

 •85. Eudialyte, imbedded crystals, 2.S98 

 *86. Gehlenitc, dark greenish-grey, four-sided prisms, 3.029 

 "87. Saussurite, compact, from Corsica, including the variety of 

 smaragdite, No. 66. 3.026 

 *88. Saussurite, granular, Bayreuth, 3.253 

 "89. Saussurite, granular, Piedmont, 3.256 

 "90. Saussurite, compact, from the shores of the Lake of Ge- 

 neva, 3.343 

 "91. Spinellane, crystallized from the Lake of Laach, 2.282 

 (To be continued.) 



Art. VII. — Botanical Letters from J. J. Rousseau to M. 

 Gouan, Professor of Botany at Montpellier. Communi- 

 cated by Dr. Hooker. 



Amongst the original correspondence of the late M. Gouan, 

 Professor of Botany at Montpellier, which has come into our 



