414 



INDEX. 



oblongifolia, 50. 

 rotundifolia, 50. 

 Sandwicetisis, 50. 

 volcanica, 50. 

 Petronius Arbiter, on, 254. 

 Photographic images, observations on, 9. 

 Photography as apphed to astronomy, 386. 

 Photometer, on the, 92. 



Physics, instrument for producing great velocity in, 107. 

 Pickering, Dr. C. On sulphur vapors, 338. 

 Plants, characters of some new genera of, 48. 

 Pleiochiton^ 53. 

 Plerandra, 129. 



Pickeringii, 129. 

 Pliny the Elder, on the nature and probable cause of the death of, 



336. 

 Pnyx and Bema, at Athens, 210. 

 Polyps, classification of, 187. 

 Prepared potato, 122. 



Protozoic Age of some of the altered rocks of Eastern Massachusetts, 

 proofs of the, 315. 



Q. 



Quadrant, Hedgcock's, 378. Report on, 384. 



R. 



Report on a course of lectures, 27. 

 Report on arrangement of sections, 4. 

 Report on Hedgcock's Quadrant, 384. 

 Resolution on the death of Francis C. Gray, 349. 

 Reynoldsia, 128. 



pleiosper7na^ 129. 

 Sandwicensis^ 129. 

 Rhytidandra, 49. 

 Rice flour, 120. 



Rings of trees, unequal growth of, 235. 



Rogers, W. B. On coal basins, 69. On vertical beams of light, 81. 

 On coke, 106. On binocular combinations, 213. On the ozonom- 



