2 REVIEWS 
follows: ‘In closing I cannot refrain from a few remarks concerning 
the conditions of life at that period, especially since the prolonged 
visits which I have made to the retreating ice front in Alaska [a 
month in midsummer, and in Greenland [two or three weeks in 
August] have rendered it so much easier for me to believe in glacial 
man than it would have been without those experiences. The neigh- 
borhood of the ice border during the glacial period was probably not 
an uncomfortable place in which to live.” And again, in respect to 
conditions unfavorable to relics—‘‘When we reflect, also, upon the 
completeness with which the habitations of the modern Indians have 
disappeared, we need not be surprised at the total disappearance of 
the habitations of glacial man. Nor is it strange that well-accredited 
discoveries of his implements have so rarely been made in the undis- 
turbed gravel which gives us the surest evidence of his great antiquity. 
. Naturally, the cautious inhabitant of that time would have been some- 
what careful about venturing down into the river valleys, whose terrific 
and periodical floods were depositing the terrace gravel.” And yet 
we are expected to believe that these terrific, fear-compelling floods 
made a deposit of sand, fine gravel, and clay in which, ‘except for 
two or three feet on top, only rare pieces of gravel occur of more than 
one half cubic inch in size” (Huston). aC Hes 
Fossil Sponges of the Flint Nodules in the Lower Cretaceous of Texas. 
By J. A. Merritt. Bull. Mus. of Comparative Zodlogy at 
Harvard College, Vol. XXVIII., pp. 1-26, 1 plate, July 1895. 
This paper is the first contribution to the minute structure and 
organic remains of the flints found so abundantly in the Caprina lime- 
stone of the Lower Cretaceous of Texas. Mr. Robert T. Hill, in 
several preliminary papers, has described their geological occurrence. 
The studies set forth in this paper were based upon a few nodules 
brought to Cambridge (Mass.) by Mr. E. E. Cauthorm, from a quarry 
west of Austin, Texas. 
‘“‘The-hardness of these nodules,” our writer says, ‘‘is often greater 
than that of glass. ... In shape they are spherical, cylindrical, or 
flat; and in size they vary from two inches to a foot or more in 
diameter. The color is a dense black, with white or gray spots mixed 
irregularly through it, varying in size from microscopic to that of a 
pin-head. ‘These spots are generally replacements of organic remains, 
