Keegan : The Holly. 



59 



and very little carotin, 1*7 tannin and tannoid, some pectosic 

 mucilag-e, quinate of calcium, much starch and oxalate of 

 calcium, but no sugar and little albumenoid ; the ash amounted 

 to 4*5 per cent, in dr}' and had 30*8 per cent, soluble salts, 

 4 silica, 27*8 lime, 7 or 8 iron and manganese, 4*5 V'-O^ and 4*6 

 SO"'. In winter the starch vanishes from the mesophyll and 

 remains only in some few isolated cells in the central portion of 

 the mid-rib. The eminent xerophily of the leaf is attested by 

 the very thick double - layered cuticle and the hypoderm 

 beneath it, but the palisade-tissue, though w^ell differentiated 

 as regards number of layers, occupies only a little over one 

 quarter of the thickness of the leaf, and hence the organ is 

 only moderately heliophilous, and seems better adapted against 

 excessive transpiration, or as a storehouse of material than as 

 an instrument of vigorous assimilation. The brown shades of 

 the faded leaves are due to quinone derived from the oxidation 

 of the tannin. 



Flower and Fruit. — The small solitary or clustered flowers 

 are grouped in axillary umbellate cymes, and have a gamose- 

 palous calyx and a nonconstant gamopetalous corolla. The 

 ovary is of oval form, 3 mm. long and 2 mm. diameter ; its wall 

 is o'64 mm. thick and is made up of about forty layers between 

 its epiderms. The ripe fruit is a berry-like drupe enclosing 

 four one-seeded triangular nuts. It is composed of (i) a thick 

 wax-coated epicarp with an underlying hypoderm, (2) a mesocarp 

 of globular cells not very large, and (3) an endocarp composed 

 of an outer zone of sclerous cells traversed by strands of fibres 

 and fibro-vasal bundles, a middle zone of a ring" of fibres, and 

 an inner zone of fibres diversely directed. The seed has an 

 outer layer of thick-walled cutinised squarish cells, an inner 

 layer of thin oval cells, a thick fleshy endosperm, and a small 

 apical embryo. The pericarp contains no starch, but encloses 

 a large quantity of pectosic mucilage with tartaric and malic 

 acids and salts, also glucose, cane-sugar, tannin, a well- 

 developed and pure pigment, a violently purgative resinous 

 substance (10 to 12 berries make a good purge), and the whole 

 fruit has I'l per cent, of ash in fresh which has 46'7 per cent, 

 soluble salts, 14*1 lime, 5*3 magnesia and manganese, 2*1 oxide 

 of iron, 10-07 P'^O' and 4-9 SO". The seeds enclose aleurone 

 and oil as reserve materials, but no starch ; they ripen here, but 

 do not vegetate in the first year. 



Summary. — The Holly thrives best on rich sandy or gravelly 

 loam, or on gravel over chalk ; therein it is indigenous with us. 



1905 February i. 



