[ 488 ] 

 LXI. Intelligence and Miscellaneous Articles. 



ON THE TORPIDITY OF THE MARMOT. BY G. VALENTIN. 



nPHE object of this memoir of M. Valentin is to examine the in- 

 -^ fluence of the winter-sleep upon the production of glucose by 

 the liver. During an abstinence from food of five or six months, 

 the sugar is persistent in the livec of tlie Marmot ; from this it fol- 

 lows that there is an essential difference between the true winter- 

 sleep of the Marmot and the torpidity of the Batrachia, or the state 

 of inanition of waking animals. 



When, as is sometimes the case, the death of the animal is caused 

 by exhaustion at the end of the winter-sleep, the liver no longer 

 contains sugar. The same fact is observed in Hedgehogs which 

 have died during their winter-sleep. On the contrary, when a 

 healthy Marmot, killed at the end of its torpidity, is examined, it is 

 found that the fresh blood of the aorta and the fresh urine will pre- 

 cipitate small quantities of protoxide of copper, showing that they 

 contain glucose. 



Some authors have expressed the opinion that the liquid secreted 

 by the stomach is absorbed, and that after passing through the vena 

 porta, it produces sugar in the liver. M. Valentin opposes this view, 

 and cites several facts which speak against it. 



The author has observed a striking difference between the sugar 

 of the liver of Marmots in their winter-sleep and that of other 

 waking animals; the former is not so readily destroyed by putrefac- 

 tion as the latter. 



In conclusion he cites an observation made upon some frogs which 

 had passed four months of the winter in a dark cellar. They were 

 frozen by exposure to a temperature of -|-5° F. ; the sugar of their 

 livers did not disappear. — Moleschott's Untersuchungen, vol. iii. 



ON THE NITRURETS OF TUNGSTEN AND MOLYBDENUM. 

 BY PROFESSOR WOHLER. 



If one of the chlorides of tungsten or molybdenum be placed in 

 the closed end of a long glass tube, with dried fragments of muriate 

 of ammonia above it, and the tube be heated to redness, first in the 

 empty part, and afterwards at the end, so that the two salts may be 

 volatilized and exposed to a red heat whilst mixed in a gaseous form, 

 a complete mutual decomposition takes place, and after all excess 

 of muriate of ammonia has been driven off, the entire inner wall of 

 the tube is found coated with a speculum of a black, semi-metallic 

 substance, which may be removed partly in brittle crusts, and partly 

 in black powder. It has the same aspect with both metals, and 

 consists either of the nitruret of the metal, or of one of the amide 

 compounds of these metals. When heated in the air it burns into 

 tungstic or moiybdic acid. When fused witli hydrate of potash it 

 forms a great quantity of ammonia. — Licbig's Annalen, February 

 1858, p. 258. 



