170 Fhe American Naturalist. [February, 
about 35 members were in attendance, besides a large number of visitors 
who came to the various sessions. The proceedings as a whole were 
very interesting. The number of papers offered was too great, how- 
ever, for the time allotted to the sessions; as a consequence each 
speaker was limited to 15 minutes, involving in many cases a rather 
fragmentary presentation of the subject. This gave the meeting a 
somewhat unfinished and unsatisfactory character, for which the con- 
tent of the papers was in no wise responsible. 
The Association held two sessions for the presentation of general 
papers, on Tuesday and Wednesday mornings, and a special session on 
Wednesday afternoon for the reading of the President’s Address and 
the transaction of business. Besides this many members attended the 
discussion on the Inheritance of Acquired Characteristics, before the 
American Society of Naturalists, where the psychologists’ standpoint 
was represented in the discussion by Prof. James. The lecture Tues- 
day evening by Mr. Alexander Agassiz on Deep-Sea Soundings, and 
the reception afterwards at Mr. Agassiz’s house, were largely attended 
by the psychologists, as was also the Annual Ptr of the Affiliated 
Societies at the Hotel Brunswick, Wednesday evenin 
The session of Tuesday morning, (December 29th). was held at the 
Harvard Medical School in Boston, and was devoted more especially 
to the experimental side of psychology. The proceedings opened with 
a paper on the “ Physiology of Sensation,” by Dr. E. A. Singer, and 
one on the “ Intensity of Sensation,” by Mr. J. E. Lough. Both speak- 
ers discussed the physical bases of sensation differences. According to 
Dr. Singer, the data which yield quality distinctions are physiologi- 
cal, and depend on functional differences of the end- -organs ; while the 
intensity data, on the other hand, are physical, depending directly on 
the intensity of the external stimulus. Mr. Lough discussed various 
theories of intensity, and took the position that the intensity character- 
istic depends on the greater or lesser prolongation of the stimulus. 
The maximum intensity effect of a particular stimulus is reached only 
by passing through a series of neural effects which are the maxima of 
other lesser stimuli. With a duration less than that which is required 
to produce this maximum, the effect is a lessened intensity. The 
speaker reported a series of experiments whose results substantiated 
this view. Two slits of different breadths were arranged one above the 
other in a pendulum, so as to admit light and cast two bright images 
on a reflector. These two images were of the same size and objective 
brightness ; when the pendulum swung, they appeared at the same in- 
stant, but one lasted twice as long as the other. It was found that up 
