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some hours gradually develop itself. Nerve-fibres and connective-tissue 
corpuscles are exceedingly well shown by this method, which will probably 
come into very general use as a sort of correlative of the 11 silvering ” method 
with dilute solutions of nitrate of silver. As a general rule, what the silver 
stains the gold does not, and vice versa. — Vide Journal of Anatomy and 
Physiology. 
Development of striped Muscular Fibre. — Herr Eckhard has published a 
paper in Henle und Pfeuffer’s Zeitschrift, in which he points out, as Huxley 
and others have done before him, that this species of muscular fibre is not 
developed from cells, but from a blastema. This blastema is nucleated, but 
the nuclei takes no share in the produce by which the internuclear matter 
is converted into fibre. Eckhard has also made observations on development 
of the heart of the chick, and states that at no period can cells be seen, but 
here, as in the muscles of the skeleton, the earliest stage is a nucleated 
blastema which rhythmically contracts before fibres make their appearance, 
the latter are developed from the internuclear matter directly. Lockhart 
Clarke had previously pointed out the fact that the development of the 
cardiac muscular fibre is the same as that of the voluntary muscles. 
What is Hippuric Acid ? — An abstract of the Researches of Shepard and 
Meissner, appeared in the Centralblatt , and has been again abstracted in the 
last number of our well-edited contemporary, the Journal of Anatomy. The 
inquiries of these savants throw much valuable light on the above question. 
However, Shepard and Meissner .having entirely failed to find hippuric acid 
in the blood of herbivora, conclude that it is formed in the kidneys. This 
conclusion is supported by previous experiments of Meissner, who could find 
no hippuric acid in the blood even after the kidneys had been extirpated. 
After introducing benzoate of soda into the stomachs of dogs, they found 
benzoic acid in the blood and saliva, and succinic acid in the sweat ; but 
hippuric acid could only be found in the urine. In opposition to Kiihne and 
Hallwachs, they assert that they have satisfactorily proved that the conversion 
of benzoic into hippuric acid takes place quite independent of the liver. 
After ejecting hippuric acid into the stomach of rabbits, they found extremely 
little hippuric acid in the blood, though abundance was found in the urine ; 
on the other hand, benzoic acid and urea were abundantly found in the blood. 
When, on the other hand, hippuric acid was injected subcutaneously, 
hippuric acid was found in the blood in large quantities, but no benzoic acid. 
Hence it appears that hippuric acid is decomposed in the digestive tract into 
benzoic acid and glycocoll, the latter of which, according to Kiithe and 
Horsford, is easily transformed into urea. Meissner and Shepard have 
found in the cuticle of plants a substance having the following formula 
C 14 II 12 O 10 , which is nearly identical with the formula for cinchonic acid 
C 14 H 12 0 12 . From this substance they suppose the hippuric acid found in 
the urine of the herbivora to be derived. 
Civiale's Collection of Calculi. — Shortly before his death, M. Civiale pre- 
sented his splendid collection of calculi to the French Academy. At the 
same time he offered some important remarks upon the various forms, 
physical and chemical, of calculi. — Vide Comptes Rendus, May 13. 
A useful form of Poultice , the invention of M. Genevoix, is now on 
view at the Paris Exhibition. It consists of an impermeable tissue, enclosing 
