316 Rev. A. Irving — On the Permian and Trias. 



This is evidently the bronzite commonly found in meteorites. 

 The green mineral is the soluble part of the meteorite ; its cleav- 

 age in one direction is very perfect ; its specific gravity is 3'35 ; it 

 has a hardness of almost 7, and is readily and completely decom- 

 posed by hydrochloric acid. On analysis it was found to have the 

 composition : — Oxygen. 



Silicic acid 41-50 22-13 



Iron protoxide 14-21 3-12 



. Magnesia 44-64 17-86 



100-35 

 The mineral, therefore, is olivine. Dr. L. Smith, who has ex- 

 amined this meteorite, describes a third silicate which is opalescent 

 and of a light greenish-yellow colour, and cleaves readily. It was 

 a difficult matter to obtain enough of the silicate for analysis, but an 

 examination of 100 milligrammes gave the following numbers : 



SUicicacid 49-60 26-12 



Iron protoxide 15-78 3-50 



Magnesia 33-01 13-21 



98-39 

 Tliis is equivalent to one atom of bronzite and one atom of olivine, 

 which, he says, is "a form of silicate that we might expect to find in 

 meteorites." The nickel-iron, as has already been stated, is abundant, 

 sometimes in large nodules of from 50 to 100 grammes. It displays 

 the Widmanstattian figures beautifully, and possesses the following 

 composition : 



Iron 92-001 



Mckel... . 

 Cobalt 

 Copper 

 Phosphorus 



... 7-100 

 ... 0-690 

 Minute quantity 

 ... 0-112 



99-903 

 A careful examination for felspar and schreibersite was made, but 

 with a negative result. 



{To be continued.) 



V. — On the Classification of the European Eocks known as [] 



Pekmian and Trias. 



By the Eev. A. Irving, B.Sc, B.A., F.G.S. ; 



Senior Science Master of "Wellington College. 



{Concluded from p. 278.) 



OF the fauna of the Dijas Credner remarks that it is much poorer 

 than that of Carboniferous times, and with the exception of a 

 few reptiles and fishes, limited to the marine formation of the series. 

 Of all the lower forms Brachiopoda are by far the most prevalent, and 

 furnish the most characteristic and most widely distributed of Zech- 

 stein remains. Lamellibranchiata assume, however, an importance 

 unknown to them in earlier periods, and in their general character 

 tend more towards Mesozoic than Paleeozoic forms ; he even suggests 

 that Schizodus may be considered the ' precursor (Vorlaufer) of the 

 Trigonim.' Gasteropods are limited to a few genera and 20 species, 



