52 QUARTERLY CHRONICLE. 
whether it is possible that these forms should be repeatedly 
produced by heterogenesis, considering that the presence of 
ova and zoospores in the air is the true explanation of the 
phenomena. A very pleasingly executed plate illustrates 
Mr. Samuelson’s paper. 
Observations on the Structure of Ameba and Actinophrys.— 
Recently, at a meeting of the Boston Society of Natural 
History, Dr. Wyman gave an account of some Amecebe which 
he had obtained in a rather remarkable manner. They ap- 
peared first as minute points, and gradually developed, in 
some fibrine placed with water, between two plates of glass, 
for the purpose of observing its decomposition. They ap- 
peared to consist of a simple sarcodic mass, in which granules 
were numerously imbedded; these passed out of the Amcebze 
with great freedom, and Dr. Wyman was inclined to consider 
these animals as deprived of any proper integument. Dr. 
Henry James Clark was inclined to disagree with Kolliker 
as regards the homogeneous nature of Actinophrys, consider- 
ing the vacuoles displayed in that animal as true cells. Dr. 
Clark had observed these cells with an objective of 150 de- 
grees angular aperture, made for him last June, by Tolles, of 
Canastole, New York, with which he had no difficulty in 
working, through a sufficient depth of water to cover the 
Actinophrys, and he states that he could readily detect the 
walls, not only of the superficial but also of the innermost cells. 
Professor Clark, who communicates an account of this dis- 
cussion to the ‘Ann. and Mag. Nat. Hist.,? November, 1864, 
draws particular attention to the angular aperture and work- 
ing distance (th of an inch) of this objective. He also 
Jo 
briefly states his views on the production of vibratile cilia, 
which he considers to be produced in the amorphous inter- 
cellular substance, as also the “ cuide ” of Coelenterata. 
On the Formation of Coral. By M. Lacazn Duvruters. 
(‘ Quart. Journal Science,’ iv, 1864.)—A series of investiga- 
tions were recently undertaken by M. Duthiers on this 
subject, for the purpose of prosecuting which he has been 
spending some time on the coast of the Mediterranean. 
In the present paper he speaks first of the observations 
of Peyconnel rejected by the French Academy, and complains 
bitterly that so notable a discovery as the true nature 
and affinities of corals with the animal kingdom should 
thus have been transferred from the archives of France to 
those of England. In tracing the development of the red 
coral M. Duthiers had considerable difficulty, in consequence 
of the apparent impossibility of retaining the ova of the 
polyp in a state of vitality. He, however, at length succeeded, 
