CONCHOLOGICAL WRITINGS. 71 
| Alasmodon complanatum, for instance. I shall describe here, only 
those which IJ have now before my eyes, and with the names given 
them ten years ago, at their discovery; I have seen a few others, 
which I delay to describe, not having them now in my hands. Those 
who shall purchase these new shells, may have the pleasure to give 
splendid figures of them, if they like. 
- Since 1820, several American Conchologists have attempted to 
notice, describe, or figure these shells; Barnes, in 1823, Lea, Say, 
and Eaton, later still. They had a fine field before them, in elucida- 
ting them by good figures, and describing the new kinds; but led 
astray, by various motives, they have neglected to verify, or properly 
notice my previous labors, although they were known to them. Mr. 
Say is, above all, inexcusable. I had respectfully noticed, in 1820, 
his previous labors; but he has never mentioned mine, and knows 
so little of the animals of these shells, as to have mistaken their 
mouth for their tail, and their anterior for the posterior part of the 
shells! 
If he had seen these animals alive, feeding, moving, and watched 
their habits as I have done repeatedly, he would not have fallen into 
such a blunder. The mouth is always-near the cardinal tooth, and 
the lamellar tooth is to the right of it in the right valve, to the left 
in the left valve.-—QOthers pretend that my monograph is too intri- 
cate; it is the subject which is such; whenever many species belong 
to a tribe, many divisions and sections are needed to elucidate and 
[2] 
isolate the species. All the great naturalists know and do this. 
The works wherein their erroneous labors are found cost above 
$100! (mine only 50 cents.) This has put it out of my power, as 
yet, to verify all their mistaken and synonymous names. A complete 
synonymy of these shells will soon be required, which I may perhap¢ 
undertake in future, unless it is done by Mr. Poulson, who has trans- 
lated and means to publish my monograph of 1820. Thiscontinua- 
tion will be a supplement to his translation. I mean to give in it 
my shells under my own names, imposed as soon as found in 1821 
and 1822 chiefly, the undoubted right of a previous discoverer and 
explorer. If some of them are already well named and described, 
let their names be compared and the oldest or best prevail, as those 
of my old Monograph ought in all cases. C.S. R. Philadelphia, 
Oct. 1831. 
