xx MEMOIR. 
the Terrestrial Mollusks of the United States, 
which he made a special study. As long ago 
as 1835, he commenced a monograph of this 
group of animals, and published it, from time to 
time, in the Journal. Besides his papers pub- 
lished in the Journal, he read others to the 
Society, of no less interest and importance, on 
various subjects, in which he displayed most just 
and discriminating views of the claims of Natural 
Science, and of the spirit and aim with which it 
should be prosecuted. 1 
1 The following; are some of the papers found on his files : — 
Report on the Journal of the Academy of Natural Sciences, Vol. VII. 
Part 2, 1S37. 
Remarks on the Reports on the Birds, Fishes, and Reptiles of Massachu- 
setts. November, 1839. 
Observations on the Appearance of the so-called Sea Serpent at Nahant, 
as seen by himself, August, IS39, with sundry Documents. 
Criticism on Schlegel's Notice of Dr. Holbrook's Herpetology, Vol. I. 
September, 1840. 
Remarks on two Paleontological Works of Michelotli. October, 1S42. 
Observations, during two successive summers at Nahant, on the Habits of 
the short Sun-fish, ( Orlkagoriscus mola.) December, 1S42. 
Remarks on the American Species of Pupa. April, 1843. 
Remarks on the Descriptions of New Fresli Water and Land Shells, by 
Isaac Lea. 
On the Hydrarchos and the Mastodon, (published in the Daily Advertiser, 
September, 1S45.) 
Remarks at the Annual Meetings of the Boston Society of Natural His- 
tory. 1844 and 1845. 
Remarks on the Fossils from the Strata of the Bluffs at Natchez, on the 
Mississippi River. April, 1S46. 
