296 ROCHESTER ACADEMY OF SCIENCE. [JunC 25, 



lowing spring ; others believe that it is necessary that they be thor- 

 oughly dried before they will develop. I will only say that in my 

 experience, I am sure of finding Vohwx in its season in certain ponds 

 that dry up in the summer, but not at all sure of finding them else- 

 where. 



The fish-like odor emitted by Volvox during the sexual process of 

 reproduction, is, without doubt, somewhat analogous to the odor 

 emitted by flowering plants when in bloom, and like that, this odor 

 is present at no other time.* 



The writer in the company of an honored member of this society 

 has, on several occasions within the year, visited a pond, the waters of 

 which were teeming with Volvox, frequently fully five hundred to the 

 cubic inch of water, and yet there was no suggestion of an odor aris- 

 ing therefrom, neither during the development nor the decay of the 

 plant. It is a fact that Volvox emits the fish-like odor only during 

 periods of reproduction by the sexual process. It is a further fact that this 

 sexual reproduction does not take place annually, but only on rare 

 occasions at intervals of several years, and has not occurred in this 

 vicinity since 1888. It is, therefore, not a regular alternation of gen- 

 eration, but a form of revivification. 



In noticing the movements of a Volvox, one is often impressed 

 with the manner in which it will change its course, apparently to 

 avoid an obstacle in its path. It will advance or retreat, revolve or 

 come to rest, in as good order as did ever a Roman or Egyptian war 

 galley, under the eye of an Anthony or Cleopatra, indicating a will 

 and a purpose in its movements. Its ability in this direction is best 

 seen where the sphere has been rent or ruptured ; one may fre- 

 quently see an irregular fragment, consisting of one-tenth to nine- 

 tenths of the original sphere, moving through the water/;/ a direct line. 



*The Executive Board of this city, in its annual report for 1888-89, published a report on the 

 "Cause of the odor and taste of the Hemlock Lake water," in which there are two (juite serious 

 errors, for which the printer might have been responsible. As I have never seen these errors cor- 

 rected I take this opportunity of doing so. The principal error (on page 44) is as to the process of 

 reproduction then taking place. It was not the asexual process of reproduction, as the report 

 states, but the sexuaUox rarer) process. The other error referred to occurs in a foot-note on the 

 same page, and naturally follows the first error. These errors may seem to be of small moment, 

 but when we remember that the facts therein sought to be recorded are misstated, and therefore 

 misleading, we are not surprised to learn that [some Algaeists have even gone so far as to openly 

 question whether we were dealing with V'ohio.x glohator, in short, whether or not we knew the 

 organism. Because these facts were not made clear in the report above referred to, the correct- 

 ness of the conclusions of the Microscopical Section is unjustly questioned by other scientists, 

 and yet not without apparently good grounds for their conclusions. 



