TRANSACTIONS OF SECTION B. 



505 



the nature of an aborted organ such as a petal or stamen. It is a disputed point 

 among physiologists whether this saccharine matter is a true secretion or simply 

 an excretion of'eflete matter from vegetable cells— a bi-product of the chemical 

 changes taking place within these cells. Nectar is, of course, the source 

 whence the bee derives honey, but it also affords sustenance to many different kinds 

 of insects as well as humming-birds. The bright colours of flowers, as shown by 

 Sir John Lubbock's experiments, serve for the guidance of insects to them, and 

 the odours which they emit fulfil the same end. The markings on a flower's petals, 

 too, always converge'towards the nectar. The importance of these guides to insects 

 will be apparent from the following estimations, which show how indispensable it 

 is that as little time as possible should be lost by an insect while collecting honey. 

 It must be remembered, also, that in order to protect the nectar from rain, it is 

 usually contained in the least accessible part of the flower. The formation of 

 nectar is observed to take place most freely in hot weather. So great, however, is 

 the economy of the plant, that it is only "formed at the time when insects' visits 

 would be beneficial, i.e., when the anthers are shedding their pollen or when the 

 stigma is mature. Biologists believe that the visits of bees, butterflies, and other 

 insects have in past time exercised an important influence in modifying the size, 

 shape, colour, &c, of flowers. The following determinations are of interest as 

 showing to what extent this action goes on, and as a help towards ascertaining the 

 value of this factor: — 



Sugar in- Flowers. (Fehling's process.) 



1. Fuchsia, per flower 



2. Everlasting pea, per flower 



3. Vetch (V. Cracca\ per raceme. 



4. ,, per single flower 



5. Red Clover, perhead 



6. ,, „ floret 



7. Monkshood, per flower , 



8. Claytonia Ahinoides, per flower 



Approximately, then, 100 heads of plover yield "8 grni. sugar, or 125 give 

 1 grm. or 125,000 1 kilo, sugar; and as each head contains about 60 florets, it follows 

 that 7,500,000 distinct flower tubes must be sucked in order to obtain 1 kilogramme 

 of sugar. Now, as honey roughly contains 75 per cent, of sugar, 1 kilo, is equivalent 

 to 5,600,000 flowers in round numbers, or say two and a-half millions of visits for 

 1 lb. of honey ! 



Another point worthy of note in these results is the occurrence of what 

 appears to be cane sugar, and that in the case of fuchsia in the proportion of 

 three-fourths of the whole. This is remarkable, as honey is usually supposed to 

 contain no cane sugar, its presence being generally held as certain evidence of 

 adulteration. The question, therefore, arises whether this change, which occurs 

 while the sugar is in the bee's possession be due to the action of juices with which 

 it comes in contact while in the honey-bag, or whether on account of the acid 

 reaction of nectar it may not take place spontaneously. 



4. On the Action of Chlorine upon the Nitroprussides* By Dr. Edmund W. 

 Davy, Professor of Forensic Medicine, Royal College of Surgeons, Ireland. 



The nitroprussides are an interesting class of compounds obtained by the action 

 of nitric acid on the soluble ferro or ferri-cyanides, which were first investigated by 



* In externa in the ' Chemical News,' Vol. XXXVIII. No. 105. 



