Keegan: Chemistry of Lakeland Shrubs and Bushes. 297 



■supposed, of lecithin, which occurs chiefly in the petals and in 

 the pollen, and is transferred thereto from the leaf via the 

 pedicel ; it seems to result from the hydrolysis of a proteid 

 of the vitellin group, and supplies another illustration of the 

 somewhat morbid tendency not unfrequently observable in the 

 magnificent order Rosaceae. 



Hawthorn. Crataegus oxyacantha. The chemistry of 

 this bushy shrub may be regarded as indicative of something 

 intermediate between the two aforesaid species of Cherry. Thus 

 the flowers contain lecithin and, in addition, a powerful volatile 

 oil and resinous substance, whose odours, intermixed with the 

 decomposition product of the former, produce a distinct 

 ammoniacal bouquet. Again, amygdalin occurs here also, but 

 only in the buds and young shoots, from which it disappears in 

 time, the adult plant no longer containing it. It is singular that 

 the young leaves contain very little or no rutin, also that the 

 haws should contain much starch, and their red pigment is 

 soluble (anthocyan), though not fully developed, inasmuch as it 

 yields a green and not a blue precipitate with acetate of lead. 

 The fresh bark of the young branches contains a very bitter and 

 ill-defined substance indicative of that Rosacean decomposition 

 and impurity to which T have already adverted. 



Holly. Ilex aqui folium. Another instance of slow vegeta- 

 tion and prolonged life. The state of affairs within the hard and 

 heavy homogeneous wood may be gleaned from my notes :— 

 'May 1 1 ; much starch in pith, medullary rays and wood 

 parenchyma, no resin or fat, no phloroglucin or glucose, has 

 iron-greening tannin and a little coniferin.' There are some 

 interesting peculiarities about the bark ; it contains ilicene, 

 a hydrocarbon C 36 H 60 , which is combined with a fatty acid, 

 a tannin which resembles caffeetannin, but it precipitates gela- 

 tine and does not yield caffeic acid by the action of alkalies ; 

 also a viscid substance (probably a compound or mixture of 

 pectin and ilicene) which is separated by bruising the bark and 

 leaving it to ferment for a fortnight in a damp place, then 

 washing with much water ; if the residue be now mixed 

 with walnut oil, the well-known 'bird-lime' is obtained, well 

 fitted to ensnare the winged tribe. The analysis of the 

 4 wrinkled, keen, and gloss}- ' leaves is difficult on account of 

 the especially strong development of the cuticle ; in August 

 there is much fat and wax, but little carotin, some resin and 

 rutin, much reducing sugar, a gelatinous substance precipitable 

 by acids, very much oxalate of calcium, but only about 4*5 per 



1900 October 1. 



