242 [DECEMBER, 



I shall be much surprised if the exposition of this species, triangularis Raf. will 

 not satisfy all unprejudiced zoologists of the hopelessness of these attempts to es- 

 tablish Rafinesque's species of the Naiades. 



We come now to by far the most important part of Mr. Conrad's Synopsis the 

 dates. He commences in the first line of his Synopsis, with the avowed purpose, 

 in forming it, to supply an assumed " absence of dates and references in Mr. Lea's 

 Memoirs," and he promises to "render strict justice" to every author according 

 to date of publication. Any one unacquainted with my memoirs, would suppose 

 from this that some at least were without dates ; such is not the fact ; every one of 

 tbem running through a course of twenty-five years is dated. The record of their 

 date is in the minute book of the American Philosophical Society and the record 

 of the day on which they were read and deposited with the Society, for publication, 

 is printed at the. caption of every one of the numerous memoirs, put there by the 

 officers of the Society. The day on which all these memoirs were issued printed, 

 is not easily ascertained, and this gives Mr. Conrad a field for assigning to them 

 erroneous dates, as we shall see in the sequel. It is a mere matter of figures, but 

 it will be seen that many are wrongly put down in his Synopsis. During the first 

 ten or twelve years that I was engaged in writing these memoirs, no one considered 

 there could exist any doubt, as to an author being entitled to his discovery ; if it 

 was communicated to a learned Society, and really was a discovery. It being is- 

 sued, printed, afterwards, was considered a diffusion of a knowledge of it. The 

 Society then printed no " Proceedings" to give immediate notice of such discoveries 

 abroad. It was not until in 1838 that the "Proceedings" were commenced. After 

 this period it was generally thought best to print in the " Proceedings" the sim- 

 ple descriptions of the species in a memoir, and the whole, in extenso, was sub- 

 sequently inserted in the Transactions. 



Mr. Conrad has declared that he will not regard the date of the reading of any 

 such described species, and acting under this principle he cuts out a large num- 

 ber of my names, classifying them among the synonyms. But he is by no means 

 satisfied with this reduction. The date of a very large number is erroneous as 

 to the time of their being actually printed and circulated, as I have mentioned in 

 the first part of this paper, that is, by assuming the date of issuing the first part 

 of a volume to be that, when the last part was issued, while the first part may 

 have been circulated some years before. 



In order to occupy as little space as possible, I will endeavor to tabulate these 

 errors. To take up my species in the order in which they occur in his Synopsis 

 and correct them, seriatim, would require great space. I commence with my first 

 memoir in 1827, and proceed chronologically to 1852. 



Published in memoir 

 read before and deposit- 

 ed with the Am. Phil. 

 Soc, Nov. 2, 1827, and 

 printed in Trans., Voir 

 3, p. 259. Distributed 

 early in 18284 Noticed 

 in Sil liman's Jour. Oct. 

 129, and the Trans, 

 cited for 1827. 



Raf. is not distinct, as he says in a note that it may be a distinct species. Mr. Say 

 in his Synopsis makes scalenius Raf. and cunealus Raf. both distinct species. 



*The four other species of this memoir are given by Mr. Conrad without any date. 



fThis may be a typographical error and intended to be 1832, the same as lan- 

 ceolatus above it. Giving Mr. Conrad the benefit of this, it will still be found 

 that he has dated these two species fi ve years after they were read to the Society, 

 four years after they were printed and issued, and two years after the date of the 

 title page of the whole volume. 



| A correspondent in Cincinnati, under date of April 25th, 1828, acknowledges 

 the receipt of this paper, and comments on the descriptions and the plates, 

 and particularly the anatomical parts. He had received impressions of the 

 plates in the previous December. 



Unio lanceolatus Lea. Dated by Mr. Conrad, 1832 

 " irroratus Lea.* " f 1852 



