M. Huber on the Emigi^aticm of Butterflies. 34?S 



Oharacter of combination, semi-tessular, with inclined faces. 

 Combinations,!.^.-^^ S. ^— ^- ^ Plate III. Fig. 12. 



Cleavage, dodecahedron, imperfect. Fracture conchoidal, 

 uneven. Lustre adamantine, resinous. Colour, clove-brown 

 and reddish-brown, inclining to blackish-brown and wax-yel- 

 low. Streak yellowish-grey, sometimes inclining to smoke- 

 grey. Opaque, semi-transparent. 



Brittle. Hardness = 4.5... 5.0. Spec. grav. =: 5.91 2... 6.006. 



Compound varieties. — Twin-crystals : axis of revolution per- 

 pendicular, face of composition parallel to a face of the octa- 

 hedron. Globular and stalactitic, sometimes with fibrous com- 

 position. Crystals and imitative shapes very fine. 



The chemical composition is unknown. 



It is found in veins at Schneeberg in Saxony, in the mine 

 Kalbe, with quartz, bismuthic ochre, and native bismuth. 



3. Ilmenite. — Under this name Professor Kupffer of Kasan 

 describes * a mineral found at Ilmensee, in Siberia, as a new 

 species. Professor Gustavus Rose of Berlin, -f* and Mr Levy \ 

 have since shown that it is nothing else but titanitic iron, a 

 variety of the axotomous iron ore of Mohs. 



4. Oligoclase. — Under this name Professor Breithaupfr || 

 describes a new species of the felspar family. Its forms are 

 tetartoprismatic, like those of Albite, from which it differs in 

 specific gravity, which is = 2.64... 2. 66. In the second Num- 

 ber of Poggendorff''s Annals for ]827, Professor Breithaupt 

 says that the soda spodumene from Stockholm belongs to the 

 oligoclase. 



Art. XXVIIL— -iVb^ic^ respecting an Emigration of Butter- 

 fiies. § By P. Huber. 



In the month of August last (1826) I had the honour to 



* Kastner^s ArcJdv filr die gesafumte Naturalehre^ \82\. No. i. 



I Poggendorff's Annalen, ^c. 1827. No. ii. p. 286. 



+ Phil. Magazine, and Ann. of Phil. January 1821, p. 27. 



II Poggendorff's Annalen, ^c. 1826. No. x. p. 238. 



§ Translated from the Memoires de La Societe de Physique et d'Histoire 

 Naturelle de Geneve, Tom. iii. part ii. p. 247. 



