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Already the somewhat strong decomposition of the material 

 before us makes it difficult to decide how to class this rock. 

 However, so much seems to be certain, that it is closely related 

 to the true alnöite, though we cannot give it this name as long 

 as melilite is not proved to occur. Of all the rocks known to me 

 from literature it seems to me to stand closest to the ouachitite 

 from Arkansas, described by Williams and Kemp. The ana- 

 lysis also recalls Kejmp's, the higher percentage of soda here 

 only showing a still closer relationship with alnöite. 



The rock in the other dike is somewhat more hoiocry- 

 stalline, but in other respects shows really only the difference 

 that it is rich in small îserpentinized crystals which are un- 

 doubtedly secondary after olivine. Round these individuals there 

 are accumulated brown mica-scales. The ground-mass itself 

 consists chiefly of elongated individuals of pyroxene, together 

 with ore and some biotite; besides this there is a brownish, 

 strongly polarizing mass, but it was impossible to prove with 

 any certainty the presence of any felspathic mineral whatever. 

 The rock evidently belongs to the monchiquite group; whether 

 it should be regarded as olivine-ouachitite or receive another 

 appellation is a question that can only be decided when more 

 abundant material has been collected and examined. 



Also the volcanic breccia in the little mass of rock is closely 

 allied to the preceding types. I could not point out olivine 

 with any certainty: fine grains of ore perfoliate the mass still 

 more abundantly, and the real, compact ground-mass, presumably 

 rich in calcite, is so weakly double refractive that one is in- 

 clined to think it to be partly vitreous. Large isolated rounded 

 grains of felspar probably derive from melted abyssal rocks. — 

 In this connection may be mentioned the large round grains 

 of brown mica that occur here and there: here it is evidently 

 the rock's own large crystals which have afterwards been partly 

 melted or corroded. 



It is impossible to say anything more precise about the 



