52' P50GRESS OF MICEOSCOPICAL SCIENCE. [^^Soum^i, S^fff ^ 
tected from light by a shutter, the object is now caught at the right 
moment, the shutter turned aside by means of a milled head, and 
the plate exposed for a suitable time. Even during exposure the 
object on the stage can be watched in the usual way through the eye- 
piece of the instrument without in any way interfering with the pro- 
cess." Our readers will perceive that the principle is the same as 
that employed in illuminating opaque objects under high powers. 
The Structure of the Pancreas. — In a memoir presented to the 
Academie des Sciences on the 31st of May, M. Giannuzzi stated the 
results of his observations on the pancreas. They are briefly as 
follows : — (1.) The excretory canals of the pancreas have very delicate 
walls, which are lined by a cylindrical epithelium. They have not the 
same connection with the secreting follicles as the salivary ducts 
have, but they form around these a network of fine tubes, which have 
no epithelium, and which enclose in their meshes the pancreatic cells. 
They may be compared to the biliary networks. (2.) The network 
of the excreting canals of different vesicles, which form the same 
glandular lobule, form connections to constitute a common network. 
(3.) The blood-vessels follow the general course of the ducts. They 
surround the vesicles, as capillaries which lie in the meshes of the 
network of ducts. (4.) The pancreatic vesicles have no wall. (5.) 
The pavement-epithelium of the vesicles is formed of flattened cells 
with a nucleus and prolongation. They are very like those of the 
salivary glands, but the nuclei are more readily seen, and the contents 
are more fatty and granular. (6.) The injections of the pancreatic 
canals were made with Prussian blue, and that of the blood-vessels 
with gelatine and carmine. The apparatus employed was the pressure 
apparatus of Ludwig. 
The Histology of the Lips of the Infant. — In a paper lately presented 
to the Vienna Academy, Herr Klein gave an account of the struc- 
ture of the lips of the new-born child. The histologic structure of these 
organs allows of three regions being distinguished in them, which are (1) 
the epidermal region, (2) the region of transition, and (3) that of the 
mucous membrane. The buccal cavity of the new-born child exhibits 
towards its anterior portion conical papillae elevated a millimetre 
above the surface of the epithelium of the mucous membrane. The 
author describes a new system of muscular fibres distinct from the 
annular fibres of the sphincter of the mouth, and from the fibres 
penetrating the cutis, described by Herr Langer. 
Fossil Bryozoa. — At the meeting of the Kaiserliche Akademie of 
Vienna on the 17th of June, Professor Eeuss read a notice upon " The 
Bryozoa of the Tertiaries of Kischenew in Bess- Arabia." 
The Origin of Bacteria. — A memoir on this subject has been written 
by Dr. Polotebnow, of St. Petersburg. The chief results arrived at 
by this observer were communicated to the Vienna Academy at its 
meeting on the 3rd of June by Professor Wiesner. The author states 
that Bacterium, Vibrio, and Spirillum are all developmental stages of 
Benicillium glaucum. The formation of Vibrio from PenicilUum may 
be observed when the spores are maintained at a high temperature. 
