220 GENEVA SOCIETY OF PHYSICS AND NATURAL HISTORY. 



which is formed by the action of ethylene upon an alcoholic solution 

 of iodine heated to a temperature of 05° 0. (149° F.) This compound had 

 been regarded by M. Baumstark as a derivative of ethyledine, and as 

 being possibly a singular iustanceof transposition. M.Demole undertook 

 the synthesis of this substance, making glycol his starting-point. The 

 substances he employed wore all prepared at low temperatures. They 

 were glycol, iodinated glycol, monethylic glycol, and iodethylic glycol. 

 Now this last agrees in its properties, its formula, and its vapor-density 

 with the said compound in such a manner that we are forced to consider 

 the latter a derivative of ethylene. 



4. Geology. — Professor Favre presented to the society his chart of the 

 Swiss glaciers of the Glacial i)eriod, projected on the scale of -as^oo* 

 This beautiful chart shows, 1st, the ne'res (partially congealed snow); 

 2d, the true glaciers of the Rhone, the Aar, the Eeuss, the Linth, and 

 the Rhine ; and, 3d, the glacial terrain or glacial clays and sediments, the 

 moraines, and erratic blocks. M. Favre designates as glacier reservoir 

 (glacial basiu) the zone of the neves occupying the high valleys, and 

 glacier cPecoiilement (flowing glacier) the zone of glaciers properly so 

 called extending along the plains. As to the glaciers of the Rhone and 

 the Rhine, the extent of the glacier reservoir was found equal to that of 

 the flowing glacier. In addition, M. Favre deduced the depth of the 

 glaciers from the position of the most elevated of the erratic blocks. 



o. Botany. — We were presented by M. C. de Candolle with the result 

 of his anatomical and physiological researches on the Dioncea muscipula, 

 which led him to adiuit that here also, as among sensitive plants, the 

 movement of the valves of the leaf is caused by the known phenomena of 

 turgescence. It is only by the touch of one of the three hairs that the 

 movement of the two demi-limbs is produced about the middle rib ; for 

 if the surface of the leaf is touched, the two valves do not close at all. 

 It was therefore in the structure of the costa, and especially in that of 

 the hairs, that M. C. de Candolle sought and found the details of cellular 

 organization, which enabled him to refer the phenomena to the effects of 

 turgescence. This work, accompanied by two plates, was inserted in 

 the Archives, No. 220, p. 400. 



6. Zoology. — Dr. Fol communicated to the society the principal results 

 of his investigations into the nutrition, the mode of reproduction, and 

 the means of locomotion of the Tunicates. These marine animals take 

 nourishment by means of a thick and glutinous saliva. Their repro- 

 duction is complicated, for it is not until the third generation that the 

 mother-form exactly reappears. The central style bears two kinds of 

 buds : the central, attached directly to the axis, jierform the functions of 

 procreation and locomotion ; and the lateral, further removed from the 

 axis, whose office had not been known, are only organs of nutrition and 

 respiration. When separated from each other, they soon perish. - Dr. 



