[From THE AMERICAN JOURNAL OF SCIENCE AND ARTs, VOL. V, JUNE, 187 3.] 
Remarks on certain Errors in Mr. Jeffreys’s Article on “ The 
Mollusca of Europe compared with those of Eastern North 
America ;” by A. KE. VERRILL.* 
In the October number of the Annals and Magazine of Natu- 
ral History, Mr. Jeffreys published an article upon this interest- 
ing subject, in which many important errors occur, due, no 
doubt, to the fact that the distinguished author is much less 
familiar with American than with European shells. But as the 
dredgings in connexion with the investigations of our fisheries 
by the U. S. Fish Commission were under my superintendence 
during the two past seasons, and Mr. Jeffreys alludes to the 
fact (though rather indefinitely) that he, by invitation of Pro- 
fessor Baird, accompanied us on several dredging-excursions in 
1871, it seems necessary that I should point out some of the 
more important of these errors, lest it be supposed by some 
that the same views are held by me. 
It is not my intention to discuss at this time the numerical 
results presented by Mr. Jeffreys; but I would remind the 
readers of his article that the regions compared are in no respect 
similar or parallel, and that it is scarcely fair to compare the 
shells from the entire coast of EKurope with those from about 
200 miles of the coast of New England, where the marine 
climate is for the most part more arctic than that of the extreme 
north of Seotland—and, moreover, that the last edition of 
Gould’s “Invertebrata of Massachusetts” contains only a part of 
the species added to our fauna since the first edition was pub- 
lished in “1841, and very little of the great mass of facts in 
regard to distribution, &., which have been accumulated by 
American naturalists during the last thirty years. Conse- 
quently that work is far from being a good “standard of com- 
parison.” To make a just comparison, all the shells on our 
coast, from Labrador to Florida, should be compared with those 
of Europe. 
And without going into a long discussion of his peculiar 
views on the geographical distribution of our shells, | would 
* From the Annals and Magazine of Nat. Hist., TV, vol. xi, p. 206. 
