266 A, Hyatt on the Beatricea. 
He, however, probably did not possess so fine a series of 
natural sections as it was our good fortune to collect, or he oe 
have discovered the very considerable differences which exist in 
their internal structure, by which they may be as readily distin- 
guished as by the external characters. I think, therefore, it may 
not be amiss to redescribe the = Sa giving such peculiarities 
as have not already been mentione 
ORDER CERIOLITES, Hyatt. 
Famury CERIOLIDA, Hyatt. 
Genus Bearricea, Billings. 
the breadth we the who le ‘ghel The coniform layers are ml : 
parallel; the inclination at the lower part, as they trend outw 
to the circumference, being decreased very slowly. The external 2 
points, The size, as pee as could be inferred from fraguet : 
B. adda isa much larger species, one fragment found by 
the npneeees being thirteen and a half feet long, by eight 
a half inches in diameter at the larger end, and judging by the : 
eration of the sides, the length of the entire shell, when 
iving, was certainly not less than twenty feet. The cham 
are very small, frequently in adults not occupying 
same parts in Beatricea nodulo 
The exterior is granulated aod ornamented by 
prominent longitudinal ridges and intervening bro 
channels. 
Cambridge, Mass., Dec. 6, 1864. (Residence, Baltimore, Md.) 
ad, shallow 
aie bes 
more than ' 
one-tenth of the transverse diameter. The coniform ang : 
ten or more ‘2 
Bee Sears bee es Bie Satay’ eA ao 
Yelg Wee 
