93 



corners sharp. But the crystals are quite dull and earthy on 

 the faces as well as on the fracture. Their hardness is some- 

 times so slight that pieces of them can be crushed between 

 the fingers. In colour the pseudomorphs are brownish grey to 

 yellowish grey. 



In microscopic sections no trace of the original eudialyte 

 substance can be detected. The whole forms an aggregate of 

 various minerals. Among these — as also in the only partially 

 altered eudialyte — we find: aegirine in more or less distinct 

 individuals, zeolite in fibrous aggregates. zircon(?), and hydrated 

 iron oxide. Besides these, there also occurs quartz in grains 

 large enough to be perceptible to the naked eye. 



19. Catapleiite. 



This mineral was discovered nearly 50 years ago in the 

 islets of the Langesund -Fjord in Norway. No other locality 

 for catapleiite was known, until the existence of the mineral in 

 the Lülzen collection had been determined. This collection 

 contained only a small quantity of catapleiite, and though the 

 material afterwards collected by me at the Greenlandian locality 

 is somewhat richer, catapleiite must, however, still be re- 

 garded as a mineral of rare occurrence on Narsarsuk. In the 

 Liitzen collection only one kind of catapleiite crystals was 

 found ; to this kind belong also the majority of the crystals 

 found by me. Besides these, however, I have at the same 

 time collected on Narsarsuk catapleiite crystals of two other 

 kinds, so that at present there are three distinct types of the 

 mineral. 



Type I. 



To the first type are referred crystals of the kind that was found 

 in the Lützen collection, and which I have described in my 

 article on this collection. Such crystals, mostly detached single 

 individuals or small groups and fragments, were met with at the 



