OF ARTS AND SCIENCES. 33 



On motion of Professor Gray, it was voted that the report 

 be accepted, and that the committee be requested to continue 

 their labors. 



On motion of Mr. G. B. Emerson, it was voted that the 

 subject of the preservation of the meteorological papers of the 

 Academy be referred to the same committee. 



The Publishing Committee, to whom had been referred the 

 subject of publishing a photo-lithographic copy of the papyrus 

 in Dr. Abbot's Egyptian Museum, reported progress, giving 

 details of the probable extent and expense of the work. Pro- 

 fessor Lovering stated that it was Professor Felton's wish 

 that the publication might be postponed, as he expected to 

 be absent from the country during the coming summer. 



Professor W. B. Rogers addressed the Academy on the 

 efflux of gases from a cylindrical orifice. He stated that the 

 fluid escaped in the form of rings, each section of the ring 

 revolving in its own plane. 



Professor Jeffries Wyman referred to certain experiments 

 he had made, to ascertain the nature of the impression made 

 by falling masses of water on plastic clay. He found that, in 

 falling, the drops became rings, the section revolving inwards 

 and upwards in its own plane, as indicated by the impression 

 in the clay, its inner edge being higher than the outer, and 

 marked by converging lines. 



Professor Rogers explained the method by which this phe- 

 nomenon resulted, as he thought, from the mechanical forces 

 called into operation. 



Professor Gray then presented the following communica- 

 tion : — 



Notes upon some RiibiacecE, collected in the United States South- 

 Sea Exploring' Expedition under Captain Wilkes, ivith 

 Characters of Neiv Species, 8fc. 



1. Timonius, Bohea, and so77ie other Guettardece. 

 These two genera were confused by De CandoUe, and have not been 

 satisfactorily cleared up by Ivortlials, who occupied himself with them 

 several years ago, nor by Miquel, who, in his Flora of Netherlands 



VOL. IV. 5 



