DATES OF CONRAD. 
221 
erences accompany the descriptions in the text from plate 
15, fig. 1, to plate 20 [misprinted 29], fig. 5. In the subse¬ 
quent reprint plates 15 to 18 were supplied, but those num¬ 
bered 19 and 20 were never published. In one of the copies 
of Conrad in the library of the Museum of Comparative 
Zoology, at Cambridge, Mass., there are bound up two plates 
numbered 19 and 20, which were probably proofs of plates 
intended to complete the series, but which were never issued. 
They illustrate some of the species in Part 3, but also some 
not mentioned there and not all of those which are men¬ 
tioned in the original. 
Number 3 was printed under Morton’s supervision from 
manuscript forwarded from Conrad during his absence in 
the South. The specimens sent by Conrad were partly dis¬ 
tributed to his subscribers to the collecting fund and the 
remainder offered to the public, as above noted. September 
3, 1833, “ Mr. Conrad’s work, 4 Fossil shells of the Tertiary 
.formation,’ ” is noted on the records of the Philadelphia 
Academy as presented to their library. It is presumed that 
the gift included Nos. 1 to 3. 
Part 4 appeared about two months after Mr. Lea had pre¬ 
sented (August 27, 1833) a notice of his manuscript work to 
the Academy of Natural Sciences. Mr. Lea’s work appeared 
early in December, 1833, about five weeks after the publica¬ 
tion of Say and Morton’s issue, and, of course, is subsequent 
in point of time; though the descriptions in Conrad’s Part 
4 are so brief—each rarely more than three lines of type, 
often without measurements and with no figures, quite un¬ 
identifiable in many cases without the specimens—that it is 
doubtful whether they are really entitled to priority, as 
against the much more careful and, for the period, admira¬ 
bly illustrated work of Lea. A copy of Lea’s work was pre¬ 
sented to the Academy by the author December 10, 1833, 
according to the manuscript record of the Society made at 
the time. 
In Part 4 the general title heading the cover is the same 
as in the previous numbers. The cover is of yellow paper. 
