208 



Mr. Edward Cabot presented a rock, found in Brookline, 

 consisting of pudding stone under sandstone. 



It presented on its surface several parallel ripple marks of 

 great regularity. He did not think them artificial, as it was a 

 stone little used in the arts. Some gentlemen supposed them arti- 

 ficial, from the curve being the same in each groove, and from 

 the worn appearance of the pebbles. Mr. Bouve thought they 

 were true ripple marks from the appearance of the curves, being 

 more depressed on one side than the other, from the substance 

 being fine at the surface and coarse at the bottom. Mr. Whitney 

 and Mr. Desor remarked that such ripple marks are very com- 

 mon, and may be seen forming under our very eyes on the shores 

 of Lake Superior. 



Dr. Cabot announced the addition to the Cabinet of 

 sixty-four mounted birds. Among them were two speci- 

 mens of Buteo Pennsylv aniens, old and young, the first pro- 

 cured in this State, except one by Dr. Shurtleff at West- 

 field ; Sirix pratincola, the common barn-owl, from Sur- 

 inam, presented by Dr. Cragin ; it resembles the aS. Javanica 

 more than jiammea ; the tarsi are larger, and the spots on 

 the breast more distinct. He also alluded to the resemblance 

 of Picus tridactylus to P. hirsutus and F. arcticus, as shown 

 by specimens of the three birds. Mr. Gray has made the 

 Parus Hudsonicus only a stage of plumage of P. atricapil- 

 lus ; Dr. Cabot could see no good reason for this opinion ; 

 we have the latter here in every stage of plumage, and it 

 never resembles the former. Mr. Eliot Cabot remarked 

 that the habits and note of these two birds are entirely dif- 

 ferent, and that he should think it hardly possible to con- 

 found them. 



Dr. Storer presented, on behalf of Capt. Atwood, a speci- 

 men of Seriola zonata, which is exceedingly rare north of 

 Cape Cod. Dr. Kneeland announced the addition to the 

 Cabinet of mounted skeletons of Rhea Americana, Peleca- 

 nus Amei'icanus, a species of Stercorarius, Musiela lutre- 

 ola, Bradypus tridactylus^ and Boa. 



