28 



Stance might be of some value in the classification of fishes. 

 The tubes grow larger and larger as they approach the heart. 

 They open into the circulating system near the heart. Prof. A. 

 had injected the heart through these tubes, and had drawn blood 

 from them by a syringe. He had injected the external surface 

 through a single tube, and that whether opening near the head 

 or the tail, or in other parts of the body. He believes these 

 tubes an apparatus for the safety of fishes living at great depths, 

 to enable them to resist the great pressure to which they must 

 there be subjected. He did not deny the existence of mucous 

 tubes in fishes, for there are such, about the heads of sharks for 

 instance, from which mucus may be obtained by pressure ; but 

 he is sure, that what have been considered hitherto as mucous 

 tubes are in reality water tubes. 



Dr. C. T. Jackson made some remarks upon the drift 

 scratches and cleavage planes of the Roxbury Greywacke. 

 He gave the particulars of the directions of the scratches, 

 and measurements of the angles of the cleavage planes. 

 The former run S. 20« E. S. 24° E. S. 40° E. The line 

 of fracture of the pebbles is N. 30° E. 



Mr. E. C. Cabot mentioned a ledge of Puddingstone, in Brook- 

 line, at the cutting for the Water-works, conspicuously marked 

 with scratches in a direction N. and S. 17° E. 



Mr. Desor remarked of the same rock, that the scratches were 

 found not only on the prominent parts of the surface, but also on 

 the depressed portions, between the projecting pebbles ; while on 

 other parts they were wholly wanting. This fact is not easily 

 explained except by supposing that the presence of the scratch- 

 ing body was not great enough to affect the pebbles, which are 

 of a harder nature than the cement between them. 



Mr. J. E. Teschemacher recurred to an observation made by 

 him at a previous meeting, respecting the process of the meta- 

 morphism of rocks, for the purpose of doing justice to the earli- 

 est eflTorts of this Society, as well as to the labors of one of its 

 distinguished members. In a very long paper, read before the 

 Geological Society of France, in 1846, entitled " Studies on the 

 Metamorphism of Rocks," by M. Durocher, the author states, 



