468 E. F. Sawyer—Radiant Points of Meteors. 
Mr. Derby refers the sandstone hills of the Ereré series, 
which. surround the Devonian plain of the same name, to the 
Cretaceous, from a study of the leaves of dicotyledonous plants, 
contained in some of the beds. These hills, which are com- 
posed of inclined strata, were elevated during, or at the close 
of, the Cretaceous age, as a broad anticlinal ridge, afterwards 
denuded away in the central portion, so as to uncover the De- 
vonian plain, and leave the present series of monoclinal ridges, 
disposed in the shape of an ellipse. 
Much of Mr. Derby’s paper is also devoted to the extensive 
Tertiary deposits and the varzea of the Amazonian valley, sub- 
jects already treated of at some length by Prof. Hartt. : 
Art. LX.— First Catalogue of Radiant Points of Meteors ; 
by Epwin F. SawYeEr. 
Tue following meteoric radiant points have been deduced 
from my observations, embracing the recorded paths of nearly 
600 shooting stars, seen during the last two years (1877-8) at 
Cambridge, Mass. Among the number may possibly be found 
one or two doubtful positions, and a few strongly suspected 
and probably new showers requiring confirmation, The other 
sitions either confirm those deduced by other observers, and 
eretofore considered rather doubtful, or are those of old and 
well established meteor systems. The limits of duration of 
the several showers are naturally uncertain; the results show- 
ing only the observed duration, and not the true period, which 
important element should receive the closest attention of ob- 
servers in the future. Considerable complication has arisen 
from the large number of known radiants, and more attention 
should be given to establishing and identifying beyond a doubt 
the true positions of those already catalogued, with their limits 
of duration, than to the discovery of new and in many cases no 
doubt pseudo-meteor streams. 
The theoretical shifting of the radiant point of a shower from 
day to day as the earth changes its position, should also, it 
seems (in the majority of cases), be practically shown in deduc- 
ing the results; although the approximate character of this 
class of observations, renders it difficult to notice any shifting 
of position at intervals of less than a week. This important 
point should engage the attention of all observers, as going far 
_to demonstrate the period of long enduring showers. 
goin goinome my results, great care has not only been exer- 
_ eised in regarding the peculiarities of each individual meteor 
_ Mapped, such as length of path, velocity, magnitude, ete, but 
