THE CHEMISTRY OF THE HIVE. 
599 
small as 3oVo '^^’> forget-me-not and some 
poppies. The most commonly recurring form is a 
globe or egg-shape, covered with upstanding, blunt 
spines ; that from the evening primrose (a) is large, 
the grains being held together by abundant filaments ; 
those from the pea tribe are oblong (e) ; those 
from many of the thistles (m) sub-stellate ; and from 
the clovers (n) fusiform, dotted and marked with a 
longitudinal groove. Thus, the bee-keeper may, if 
Fig. 127.— Pollen Grains, Various. 
a, (Enothera (Evening Primrose), Magnified 120 diameters ; b, Symphytum of- 
ficinale (Comfrey), Magnified 240 diameters ; c, Helianthus (Sunfiower) ; 
d, Ajuga repta^is (Common Bugle); e, Lathy rus prate/isAv (Meadow Vetchling) ; 
/, Polygala vulgaris (Common Milkwort) ; g, Ribes ruhrum (Red Currant) ; 
h, Centaurea scabiosa (Greater Knapweed) ; i, Phlox Druminondi ; k, Fragaria 
resca (Wood Strawberry); I, Clematis Jackmanni ; m, Carduus arvensis(Cre&p\ng 
Plume Thistle) ; n. Trifolium repens (White Clover) ; o, Cheiranthus Cheiri 
(Wallflower). 
armed with a medium microscope, detect whence his 
honey is coming. If possible, he should, however, 
before determining, carefully compare the material of 
the pellets, as gathered, with that from the plant he 
imagines to be the source of supply. 
Propolis^ a resinous substance, exceedingly tenacious, 
varying much in colour, but usually a rich brown, and 
which emits a balsamic odour, is used by the bees 
both as a cement and as a varnish. With it they 
