Proceedings. 15 



to Cotteril Clough, generally without flowers ; the coralwort 

 {JDentaria bulbifera^ L.) presents another instance. Besides 

 the smaller bulbils, the Boussingaultia puts out some of its 

 branches from the stem, which, instead of elongating like 

 the other branches, have their upward growth arrested, but 

 at the same time increased laterally ; there is thus produced 

 a mass of fragile thickened branching tubers, of the size of 

 a walnut or small turnip, from which in due time fresh 

 growths of climbing stems and flowering branches will 

 proceed. In their native condition these tubers doubtless 

 act as storehouses of food for use when the plants are not 

 able to derive sufficient food through their roots, at such 

 times as the rapid upward growth of the plant compels it to 

 draw upon its reserves. Such tubers, therefore, are analogous 

 to those of the common potato, only instead of their being 

 s ubterranean, as in the latter, they are aerial. Like the potato, 

 also, each of the leaf buds or "eyes" in these tubers is 

 capable of producing a new plant ; in other words, they can 

 be cut into fragments for propagating purposes. These 

 tubers are edible, as might be expected from a plant which 

 is allied to the spinach, beet-root, and other Chenopodiacece ; 

 indeed, they have been cultivated for the table in France, 

 but they are too mucilaginous and insipid for most palates. 

 Mr. W. W. Haldane Gee, B.Sc, F.C.S., exhibited and 

 described two electrical platinum thermometers, for use in 

 the exact determination of temperatures as high as the 

 boiling point of mercury. One of the thermometers was 

 designed and constructed by Mr. E. H. Griffiths, of Sydney 

 College, Cambridge, and was used in the investigations of 

 Messrs. Heycock and Neville. {S^^ Journal of the Chemical 

 Society^ July, 1890, p. 656.) The special construction 

 consists in wrapping a very fine platinum wire in insulating 

 material in the smallest possible compass. The resistance 

 of this coil is measured, and from this the temperature is 

 calculated. The other one had been made for Mr. Gee'S 



