Notice of a Scientific Expedition. 345 



doing this, we shall commence at Peter's Point, the place on which 

 we first landed. 



Peter^s Point. — This locality will furnish the collector of miner- 

 als with Laumonite, Thomsonite, Apophyllite, Mesotype and Heu- 

 landite. 



The Laumonite is the most abundant. Its colors are white and 

 flesh red. The crystals are small and unmodified. They occur in 

 compound masses, the individuals of which radiate from a common 

 centre, forming short stellated groups similar to stilbite. They may 

 be distinguished from the latter by the. terminating planes, (as they 

 appear to be in the masses,) which stand in the Laumonite oblique- 

 ly to the lateral edges. Many large cavities, and even deep recess- 

 es may be found lined with Laumonite in a good state of preserva- 

 tion. Peter's Point is the best place to lay in a stock of Laumon- 

 ite, although it may be found very frequently at other localities. It 

 is however, more abundant here, and in a better state for keeping 

 than elsewhere. 



Apophyllite occurs both massive and crystallized. The former 

 variety is greenish and might be mistaken for phosphate of lime. 

 The faces of fracture are generally striated parallel to the faces of 

 composition. The crystallized variety presents the primitive form 

 of the species modified by replacements of the soHd angles by single 

 triangular planes similar to Fig. 39, Shepard's Mineralogy, p. 37, 

 also, in thin tables similar to Fig. 42 of the same work. The latter 

 intersect each other in all directions and stand upon their narrow 

 edges with the plane P, vertical. 



The size of those occurring under their primary form, varies from 

 one eighth of an inch to an inch and a half. They are slightly tin- 

 ged red, cleave easily parallel to the plane P, and occur in groups 

 of different sizes, and which intersect each other in the manner of 

 crystals of Chabasie. 



The collector will do well to lay in a full supply of this rare and 

 interesting mineral while at this locality ; for so far as our experi- 

 ence goes, it is not so abundant nor so fine at any other place. 



Thomsonite. — This substance is found in long slender prisms of a 

 grayish white color in compound forms, the individuals of which ra- 

 diate from a common centre. Their extreme length is about four 

 inches. 



Mesotype. — Like the former mineral, it occurs in compound ra- 

 diating masses of extremely thin individuals, more so in the last re- 



VoL. XXX.— No. 2. 44 



