SCIENTIFIC SUMMARY. 
263 
The Election in the French Academy. — The Academy has elected M. Kobin 
to fill the vacancy in the section of zoology caused by the death of M. 
Valenciennes. The other candidates were MM. Lucaze-Duthiers, Gervais, 
and Dareste. 
Structure of the Investing Tunic in the Gregarina. — A very able essay on 
the Gregarina appeared in the last number of the Microscopical Journal , 
from the pen of Mr. E. Kay Lankester. From this we learn that the author, 
although at first disposed to agree with Dr. Leidy in thinking that the 
investing tunic is double, has since altered his opinion. He has now, he 
says, reason to believe that the striations visible in the posterior sac of that 
species are produced merely by the contraction of a portion of the viscid 
material which fills it ; in fact, the investing membrane must merely be 
regarded as a dense layer of the same sarcodic material which forms the 
whole creature. The membrane which invests the whole Gregarina appears 
to be excessively thin and ill-defined, and more or less continuous with the 
viscid substance contained by it, which is denser nearer the exterior, and, in 
fact, seems to form a layer beneath the investing tunic, intermediate in 
density as well as position, which in one or two cases becomes considerably 
developed. 
The Development of the Infusoria has recently received the attention of 
Mr. James Samuelson, who has contributed an interesting memoir upon the 
subject to the Proceedings of the Royal Society. It is known that when 
vegetable infusions are exposed to the action of the air, the first infusoria 
which appear belong to the very lowest groups, and are afterwards succeeded 
by higher forms. Mr. Samuelson explains this fact by a very reasonable 
theory : that the monadine form which first appears is the earlier or larval 
stage of at least one, if not more, of the ciliated infusoria, into which it 
becomes metamorphosed in the course of development. Mr. Samuelson has 
recorded several interesting experiments, and from some of them he concludes 
that the Cerco-monades are the larvae or earlier forms of the ciliated animal- 
cules which succeed them. He desires that other experimenters should 
repeat his observations, for, though he himself has perfect confidence in their 
accuracy, he is aware of the great liability to error in such a difficult pursuit. 
The Circulation in the Lower Animals. — According to the researches 
of M. Lucaze-Duthiers, the characters of the circulatory apparatus in the 
lower forms of animal life are different from those of this system in the ver- 
tebral sub-kingdom. He has pointed out some curious facts relative to the 
blood-vessels of certain mollusks and zoophytes. He has found that the circu- 
latory system of these animals is very different from that of the higher groups. 
The blood-vessels communicate with the atmosphere and with the stomach by 
direct apertures. Hence he concludes that it is unfair to extend to the higher 
animals generalizations which have been framed in accordance with the 
structure and functions of the lower ones. — Vide Comptes Rendus, Dec. 18. 
The WorJcs of Linnaeus. — The first edition of the “ Systema Naturae” of 
Linnaeus, published in 1735, is to be reproduced through the photo-litho- 
graphic process, by the Stockholm Academy of Science. It contains the 
earliest attempt to treat man zoologically. 
Accessory Eyes in Vertebrates. — In a paper lately published in the Archives 
des Sciences , and which has been abstracted by one of our contemporaries, it 
