2 — Cincinnati Society of Natural History. 
Turspay Evenine, February 6, 1883. 
Dr. R. M. Byrnes, President, in the chair. Present, ten members. 
It was announced that the Society would receive its friends on the 
evening of February 12th, from 8 to 9:30 p.m., on the seventy-fourth 
anniversary of the birth of Charles Darwin. 
Donations were announced as follows: From G. H. French, foar 
pamphlets; Cuvier Club, fourteen species mounted birds, one speci- 
men fish; Dr. Robert Fletcher, one pamphlet on prehistoric trephining; 
Signal Service Bureau, annual report for 1880, and Weather Review; 
Ralph Colvin, four specimens manganese; Dr. J. A. Warder, five 
pamphlets; E. L. Sherwood, one specimen fossil; Joseph F. James, 
two pamphlets and one volume; Prof. H. W. Haynes, through Gover- 
nor Cox, one pamphlet on Discovery of Paleolithic Implements in 
Egypt; Arthur F. Gray, twenty-nine species shells; Smithsonian In- 
stitute, volumes 22 and 23 of Contributions to Knowledge; Mr. Rom- 
baugh, one specimen banded sandstone;-.8. 8. Scoville, M. D., two 
specimens Orthis scovillei; Ohio Mechanics’ Institute, Proceedings, 
volume 1, No. 4. : 
Turspay Eventne, March 6, 1883. 
Dr. R. M. Byrnes, President in the chair. Present, twenty members. 
Prof. A. G. Wetherby delivered an address upon the “ Relation of 
Mollusks to Their Shells,” He gave an account of the anatomy of the 
common muscle or Unio of our Western rivers. The shells of these 
mollusks grow generally in the direction of the shorter dimension or 
diameter, and hence this diameter is called by conchologists the 
length of the shell, and the longer diameter is the width. The growth 
of a shell is always from a nucleus, and this nucleus in the univalve 
shell, to which our common snails belong is a spire. In most shells 
the spire is elongated, and there is no difficulty in determining which 
side of the shell is the upper side or spire, but in Planorbis the shell is 
disciform and almost flat, so that the upper side can be satisfactorily 
determined only by the position of the animal. Prof. Wetherby con- 
cludes that the shell in this genus is reversed, and the spire carried 
with its apex downward, an anomaly in the family of Mollusks. 
Mr. A. F. Gray was elected a member of the Society. 
Dr. k. M. Byrnes exhibited a specimen of Stellipora antheloidea, 
collected from the Utica Slate Group, within fifty feet of low-water 
mark in the Ohio river opposite the foot of Fifth street, 
