28 MUSEUM OF COMPARATIVE ZOOLOGY. ([Feb. 
them in good preservation. In the exhibition rooms there were 
about 500 species of crustacea, mostly determined by Messrs. 
Dana, W. Stimpson and others; all the rest had been stored 
for some years on the cellar shelves in kegs or glass jars. 
During the first three months I was occupied in cleaning, sepa- _ 
rating, and unpacking these jars. In this time, with the excep- 
tion of some kegs containing mostly duplicates, the whole col- 
lection was assorted in 4,300 glass jars; these jars were filled 
with new alcohol and placed on provisional shelves put up for 
the purpose in the library and adjoining rooms ready for scien- 
tific purposes. The following months I was engaged in a gen- 
eral revision of the whole collection, nearly three-quarters of 
which consisted of Brachyura and Macrura, now arranged in 
families and genera. Some families are even farther revised, 
especially the Stomatopods, as well as some genera of the 
Brachyura and Pagurina. The very valuable collection of the 
American Astaci is monographically finished and now in the 
way of publication. An estimate made upon this careful 
revision shows the collection to contain more than 2,000 
species, a considerable number when we remember that accord- 
ing to the most recent computation of the species of crustacea 
thus far known they do not exceed 5,500 species. 
Meanwhile I formed a small but valuable collection of the 
family of Pseudo-scorpions, hitherto neglected in the study of 
the American fauna. By the help of Messrs. Francis Sanborn, 
Cresson, Packard, Burgess, Mann and others, I was able to bring 
together a collection of species from all the recognized genera 
of these interesting animals, hitherto unknown on this side of 
the water, with the exception of two species described by Mr. 
Say. Mr. Menge, of Danzig, Prussia, to whom we owe the 
best monographs of this family, was so kind as to present the 
Museum with a full set of his types. A monograph of this 
small family containing a complete synopsis of all described 
species, with drawings of all American species, is nearly ready 
for publication. 
In the succeeding months the Insects, Myriapods and Arach- 
nids in alcohol were revised, cleaned, and partly separated, and 
repacked in new alcohol. Mr. Burgess has had the kindness 
to revise, determine, and catalogue the North American Myria- 
