1881. ] Scientific News. 507 
and the opportunities they have presented are considered, have 
not been many, but all published possess permanent value. ey 
date from 1854, and number some eleven titles, The first con- 
sists of notes on “A/as. (Marg) marginata,’ published in 1854. 
In 1856 he published three papers, two in the Proc. Bos. Soc. Nat. 
Hist. and one in the Proc. Acad. Nat. Sci., all relating to the Mol- 
lusca of the State of New York, and two of them are local lists, 
with notes. In 1857 he published a single paper “On Erosion of 
Uniones,” in Proc. Bos. Soc. Nat. Hist. In 1860, two papers, one 
on “Colors of Unionidz,” and the other a local list, both of which 
appeared in the Proc. Acad. Nat. Sciences of Philadelphia. He 
published nothing further until 1868, when appeared a paper in 
the dm. Four. of Conchology, “On the Mollusks of the Mohawk 
valley.” In 1869, in the same journal, he published a valu- 
able paper “On the Shells of the Coosa river,’ Alabama. The 
bibliography and indices of Dr. Lea’s “Synopsis of the Unionidze” 
next engaged his attention, and they are, in great part, largely 
arranged by him. His last published work of value appears 
in the Geological Report of Alabama for 1875(?), and contains 
the almost complete geographical distribution, by streams, of 
the Shells of that State. Some very suggestive remarks are 
likewise appended as notes to the work which he has there 
performed. He was also an occasional contributor to the Nat- 
published, would add largely to our knowledge of fresh-water 
forms. The most of these have passed into the hands of my col- 
a Systematist. In this field he was an acknowledged master, and 
here his services were frequently required by individuals and freely 
Siven. He arranged and classified many public collections, among 
which were the American fresh-water shells in the Smithsonian 
Institution, the last critical revision of which was made by him; 
the collection of the Buffalo Acad. of Nat. Sci., those of Vassar 
College, Mount Holyoke Seminary, Wellesley and Hamilton 
Colleges, and the State Cabinet at Albany. The examination of 
these extensive collections furnished him with material for the 
determination of synonomy, which, had he lived to complete it, 
Would have very greatly reduced the number of acknowledged 
species. In work of this character he was truly philosophic, and 
his opinions commanded and obtained respect. The great changes 
In Scientific thought occasioned by the doctrines of evolution, 
ound an ardent advocate in him, and those great principles 
formed the basis of all his later work. He has often remarked, 
d repeated it to others in his correspondence, that the great 
Work of the future would be done from this standpoint,and “much 
remains to be done in eradicating the errors of the older natural- 
~~ € was a conscientious worker, an acute thinker, and a 
man of great research, In the prosecution of his studies he was 
