Annual Meeting.] 
6 
[May 7, 
We shall try to mount a selected series of these shells upon a 
model of the surface of the island of Oahu. The basis of this has 
been already furnished by the enlarged model of the topographical 
features of this island prepared by Mr. George H. Barton, and 
which was opportunely presented by him to the Society before the 
Gulick Collection was purchased. It will be necessary to enlarge 
this model considerably and to place it with the shells mounted in 
their appropriate locations under glass in a table case in the ves- 
tibule. With this arrangement and some other illustrations, it is, 
we think, practicable to solve the most difficult problem presented 
by the collection of Dynamical Zoology, which was to provide an 
opportunity for the study of the relations of species to the different 
physical features of the country in which they originated, and to 
give an objective illustration of what naturalists mean by the phrase, 
the origin of species by means of divergent evolution. 
Geology. 
The accessions to the collection in this department have not been 
large, about 300 specimens in all. But they consist almost wholly 
of selected material, obtained by purchase or exchange, and they 
fill some important gaps, especially in the New England collection 
of minerals, which is gradually becoming a creditable representa- 
tion of the minerals of New England. With the exception of the 
incorporation of this new material, the mineralogieal and lithologi- 
cal collections remain in the same condition as at the close of last 
year. 
Professor Crosby has, however, completed the manuscript of the 
guide to the lithological collection, and with the assistance of Miss 
Carter he has completed the arrangement and labelling of the pet- 
rological collection ; and has also written the explanatory text for 
this collection. The guide to the petrographic collections, includ- 
ing both lithology and petrology, is, therefore, now complete in 
manuscript and ready for publication. 
Although the general collection of minerals and rocks are thus 
finished, in the sense of being fully arranged, labelled, and pro- 
vided with an explanatory text, it is hoped that they will continue 
to grow through desirable accessions until eventually a revision 
of both the collections and the guides will become necessary. 
Mr. Crosby has given much attention to the New England geol- 
ogy, especially in collecting material and data for a very complete 
