





PROCEEDINGS OF SCIENTIFIC SOCIETIES. 389 
now given by those who live near the geyser. Eruptions do not occur until 
the water in the bottom of the geyser-pipe is 266° F., as shown by Bun- 
Sen’s observations. The time taken to raise the water in the pipe to 
266° F. will evidently depend upon the quantity of water poured in a 
given time through the fissures that feed the pipe. As the water is sup- 
plied by the hills near the geysers, a pes of rain readily affects the quan- 
tity of water flowing through the pipe. The greater the quantity, the 
greater will be the time between the eruptions. If the quantity of cold 
water poured into the pipe were so great that the bottom of the pipe 
It is from the enlarging of the water channels by earthquakes, so as to 
pour in more water, that some geysers that were formerly active have 
how become quiet. 
In discussing the remarks of Mr. Rusu EMERY “ ne the Boulder-field in 
Cedar County, Iowa,” Dr. C. A. Wurre and Professor Wrxcnett stated 
that there were some evidences of a northward distribution of boulders in 
Iowa and Michigan. 
Col. J. W. FOSTER alluded to the large size of the Castoroides, or fossil 
beaver, adopting the v iew of Professor E. D. Core, that it must have been 
nearly as large as the grizzly bea 
l ITTLESEY ior een the localities and eat age of the 
deposits i in which remains of. the horse had been found. Professor E. D 
Corr i insisted that though no difference had been discovered e the 
eeth of the living and fossil species of horse, yet they may be, and prob- 
ably were, of entirely cert species; the living species having been in- 
troduced by European 
MEEHAN ein: summed up the results of his studies on the Leaves 
S. nation 
in the individuals of the same species, or branches of the same individ- 
als. Many so Sy A so species of Conifer are the same; but in 
Various States of adnation. 
The next meeting of the Association will be held in SALEM, Mass., com- 
ol. J. W. FOSTE 
A New York, Vice ae Prof. Josepa LOVERING, Permanent 
Meer; Prof. O. C. Mar rabon Haven, General Secretary ; Prof. A. 
ELwyy, Philadelphia, Trasar 
Atabey OF NATURAL Scrences, Conchological Section. — Phila ladel- 
Pi, July 3, 1868.— Mr. Wm. M. Gabb called attention to the variation 
we that takes place in genera auring successive geolog ical periods. 
y MKO 3 eric: elopment 
M Species in any one age, those species beloni to other periods, es- 
ly most removed from the chronological centre of develop- 
nme tb Speak, are usually more or less aberrant from the average 
