73 



Mr. Ayres remarked that the species of Psolus, pre- 

 sented by Mr. Stimpson at the preceding meeting as pro- 

 bably P. phantapiis, was quite distinct from his own Icevi- 

 gatus and granulaius. He also stated that he had i;eceived 

 several specimens of Thyonidium from the Grand Banks, 

 and he had caught seven or eight in fathoms of water 



in Massachusetts Bay. At the time he described Botryo- 

 dactyla grandis, some two months since, the species had 

 only been obtained on George's Bank ; since then two or 

 three had been taken from the stomachs of Cod caught in 

 from twenty to thirty fathoms of water. The species found 

 by Mr. Stimpson on Chelsea Beach, he himself had 

 obtained from Cod taken in from fifteen to twenty fathoms 

 of water. These facts tended to confirm him in the opinion 

 which he had heretofore expressed, that as yet there are 

 not sufficient data for the recognition of a law of a grada- 

 tion of depth of water in proportion to the degree of de- 

 velopment of the species, in this class of animals. 



Mr. Stimpson stated that all the specimens which he had 

 procured in the month of January had the genital tubes 

 filled with ova, an indication of the breeding season. 



Mr. Ayres said that all the specimens he had obtained 

 during the past four or five months showed similar indica- 

 tions. 



Dr. C. T. Jackson exhibited two very perfect fossil 

 fishes which he had recently obtained from the rock adjoin- 

 ing the coal formation at Hillsborough, N. B. The speci- 

 mens from this locality, he said, had a peculiar interest as 

 being the first found in the coal formation in America. 

 Those exhibited belonged to two genera, carnivorous in 

 their habits. In the locality from which they were taken, 

 Coprolites were found, some with and some without scales, 



Mr. Bouve inquired whether Dr. Jackson's observations 

 confirmed the opinion of Mr. Logan, that the Siigmaria are 

 the roots of the SigUlaria. 



