74 



Dr. Jackson replied, that such is not the fact. At the 

 South loggings he had had an opportunity of comparing the 

 Stigmaria with the roots of the Sigillaria, and had found 

 them unlike each other. * The Stigmaria also is found in 

 the sandstone, not in the under clay. 



Dr. Jackson described the interesting appearance of the 

 shores of the Bay at this locality, through a distance of five 

 miles, presenting a complete geological section of the strata. 

 These are inclined at an angle of 20°, and show the trunks 

 of trees imbedded in them at various depths. He himself 

 saw a flattened stem of Sigillaria twenty feet long, and he 

 was assured by the miners that it extended at least forty 

 feet farther into the rock. As there is no sign of decompo- 

 sition, it would seem that the sand must have been rapidly 

 deposited upon them, and as the trunks of the fossil trees 

 are always at right angles to the strata, the latter must have 

 been lifted since they grew. Tiie formation consists of 

 alternate marine shales and beds of coal. The coal seam 

 which is worked is four feet in thickness, and on going into 

 the mine with a lamp one passes directly beneath the roots 

 of fossil trees. 



Dr. Bacon exhibited a donation of thirty minerals from 

 Mr. Alger. 



Dr. Burnett presented twelve minerals from the Natural 

 History Society of West Chester, Pa., and a number of 

 minerals from the Burrstone formation of South Carolina. 



Dr. Cabot presented, in the name of Miss Lydia Green, 

 a specimen of Nautilus from Fayal ; also a portion of a 

 plant of unknown species. He also announced the addition 

 to the Cabinet of ten birds received from Moses Kimball, 

 Esq. in exchange, namely : Stephanophorus ccsruleus ; Co- 

 tinga ccBrulea, Purple-breasted Chatterer ; C. Cayanu, Pur- 

 ple-throated Chatterer ; Schizornis Africana, Crested Plan- 

 tain-eater ; Laimodon diibius, Grove-billed Barbican ; Cro- 

 tophaga major, Greater Ani ; Monasa fnsca, Striped Puff- 



