ne oe 
Jan. 5, 1872.] 327 [Cope. 
supposition, in relation to the use of common potash as a substitute for 
ashes. 
I cannot close this communication without referring to the original 
subject of the revival of prematurely failing peach trees. I have con- 
tinued to apply ashes in the same manner as at first, in the autumn or 
spring, or both, to the different kinds of fruit trees; and, I believe, with 
uniformly favorable results. The peach orchard, which, four years ago, 
appeared to be in a dying state, and had for several seasons ceased to bear 
fruit, is now in a vigorous state, and last summer yielded a copious crop. 
The old apple orchard, which was so wonderfully revived two years since, 
continues apparently, except in the case of a few trees dying from old age, 
to hold all that it had gained, though we lost the crop last year through 
the destruction of the blossoms by a late frost. The pears and quinces 
of which the blossoming period differed from that of the apple, so that 
they escaped the frost, were full of fruit; and I was particularly struck 
with one old quince tree, which, before the use of ashes had borne scanty 
crops of a small, imperfect, knotty fruit, but, last year, under the influ- 
ence of ashes, was loaded with smooth and well formed quinces. 
T have not yet been able to form any positive conclusion in relation to 
the protective effect of fresh ashes against the curculio in the plum tree ; 
but I am prosecuting some inquiries in this direction, and hope before 
long to be able to solve the question either favorably or unfavorably. 
I must confess, however, that Iam by no means sanguine of the former 
result. 
ON THE FAMILIES OF FISHES OF THE CRETACEOUS 
FORMATION OF KANSAS. 
By E. D. Cops. 
(Read before the American Philosophical Society, January dth, 1872.) 
SAURODONTID&. 
Cope. Proc. Amer. Philos. Soc., 1870, p. 529. Hayden’s Survey, Wyoming, 
etc., 1871, p. 414. 
A considerable accession of material belonging to several species of this 
family, furnishes important additions to our knowledge of their structure, 
and enables me to determine their affinities with more precision than 
heretofore. The results are of value to the student of comparative anat- 
omy, and also to the paleontologist, as they appear to have been the 
predominant type of marine fishes, during the cretaceous period, in the 
North American seas, and to have been abundant in those of Europe. 
The characters already assigned to the family are confirmed by the new 
Species discovered, and many additional ones added, as follows : 
The cranial structure cannot be fully made out, but the following points 
may be regarded as ascertained : The drain case is not continued between 
the orbits, and the basis cranii is double and with the muscular tube 
