926 



SCIENCE 



[N. S. Vol. XXVII. No. 702 



river (except for a slight diversion, noted by 

 Taylor) in 3,500 years. 



From the head of Foster Flats to the end 

 of the canyon is a distance of about three 

 miles, and in the retreat of the Falls through- 

 out this section only the Erie vraters supplied 

 the river (15 per cent, of the present). While 

 receding 600 feet past the upper end of Foster 

 Flats the height of the Falls was 240 feet, 

 with rate of recession 15 per cent, of 5.6 feet. 

 The proportional time allowance was 700 

 years. Below this point, for a distance of 

 13,300 feet, there were two and three falls, 

 but the work of the upper one is now so well 

 established that it alone furnishes the data 

 necessary for computations. The mean height 

 was 105 feet, and with the volume of 15 per 

 cent, of that of the present day, the propor- 

 tional rate of recession was reduced to 0.42 

 of a foot. This increased the time required to 

 31,600 years. There still remain 450 or 500 

 feet of the gorge to its end. Here the height 

 of the Falls was 35 feet, so that their re- 

 cession, with the small volume of water, was 

 very slow, or proportionally only an eighth of 

 a foot a year, at which rate 3,200 years were 

 required. Thus, the formation of this lower 

 and older stretch of the gorge required 35,500 

 years, or 39,000 for the total recession. The 

 above figures are based on the assumption that 

 the rainfall has been secularly uniform, with 

 no greater increase of the drainage basins than 

 at present. Philip S. Smith, 



Secretary 



THE TORREY BOTANICAL CLUB 



Th^. meeting for April 29, 1908, was called 

 to order at 3:45 p.m. by Vice-president John 

 Hendley Barnhart. Fourteen persons were 

 present. 



The following abstracts were submitted by 

 the authors of the papers presented: 



The Boleii of the Forest Herlarium: William 



Alphonso Murrill. 



This paper will shortly be published in full 

 in one of the periodicals of the club. 



Suggestions for Future Worh on the Flower- 

 ing Plants of the Local Flora: Roland M. 



Harper, chairman of the Phanerogamic 



Division of the Committee on the Local 



Flora. 



There is probably not another spot in North 

 America which has so many different kinds 

 of country within a short distance of it as 

 New York City. In consequence of this geo- 

 graphical diversity there are found within one 

 hundred miles of here over one half of the 

 species of flowering plants credited to the 

 northeastern United States and adjacent 

 Canada. 



The earliest botanists in this region had 

 their hands full with merely collecting, classi- 

 fying and describing the plants. After nearly 

 all the species had been described the next 

 step was to record the known localities for 

 each, and to prepare " floras " of certain lim- 

 ited areas. Since the middle of the nineteenth 

 century a great deal of attention has been paid 

 to anatomy, physiology, pathology and crypto- 

 gamic botany. Nomenclature was a leading 

 topic for discussion among botanists a decade 

 or two ago, and a little later ecology came into 

 prominence, but for various reasons the latter 

 has not proved very attractive to amateurs, at 

 least here in the east. Experimental evolu- 

 tion is now attracting considerable attention, 

 but there are very few persons qualified for 

 this kind of research. 



At the present time amateurs seem to be 

 doing very little to advance our knowledge of 

 the local flora, but there is no good reason 

 why this should always be so. Notwithstand- 

 ing the inroads of civilization, and the vast 

 amount of botanical work that has already 

 been done in this vicinity along certain lines, 

 there are still awaiting solution here innumer- 

 able problems which can be successfully at- 

 tacked by any one possessed of a fair knowl- 

 edge of plants and a little spare time. 



Very little of the vegetation of this vicinity 

 has been described, still less photographed, our 

 natural habitats have hardly been classified, 

 and some of them have never even been ade- 

 quately defined. Our dunes, marshes and 

 Palisades, the pine-barrens of Long Island and 

 New Jersey, and various other easily accessible 

 places have been little damaged by civiliza- 

 tion, and offer a fertile field for study, but the 



