428 



A paper for publication in the Society's Journal was received 

 from Prof. James Hall, entitled " Descriptions of New Species of 

 Crinoidea and other Fossils from the Carboniferous Rocks of the 

 Mississippi Valley." It was referred to the Committee on Pub- 

 lication. 



Dr. C. T. Jackson presented some fossil shells from the 

 coal formation at Chiriqui, which is of Eocene age and 

 apparently equivalent to the Paris basin. 



The thickness of this coal is about 73^ feet, of which 30 feet 

 are so near together as to be worked in a single gallery. A broad 

 belt of this coal extends through British Guiana and Costa Rica, 

 the more southern portions having been examined by D'Orbigny, 

 Darwin, Wheelwright and other French and English naturalists ; 

 the true coal series, however, has never been discovered in South 

 America. This coal in quality is almost identical with cannel ; 

 in specimens analyzed from different localities, the carbon varied 

 from 39 to 43^- per cent., the gas from 41 1^ to 48^, the water 

 from 5 to 6, the ash from 6J- to 10, and the specific gravity from 

 1.316 to 1.341. In the elementary analysis of a specimen from 

 Cultivation Creek, we have : 



Carbon 68.018 



Hydrogen ...... 6.480 



Oxygen ...... 17.858 



Nitrogen ...... .855 



Sulphur ...... .189 



Ashes ...... 6.600 



100.000 



A microscopic examination of this coal shows that it was formed 

 from cellular and not from exogenous plants. Pope's Island coal 

 resembles some varieties of lignite, but contains bitumen ; its odor 

 in burning is like that of amber. This coal burns like the cannel 

 of Scotland, with an abundant yellow flame. 



Mr. Robert Chambers, of Edinburgh, was elected a 

 Corresponding Member, and Dr. C. F. Crehore, of Boston, 

 and Mr. J. Haven Emerson, of Cambridge, Resident 

 Members. 



