THE PRINCIPLES OF BOTANY. 
505 
Average Composition of: 
Sc^ns 
Nitrogenous flesh-forming matter . 23*30 
Non -nitrogenous substances, starch 
&c.—heat givers . . . 58*50 
Ashes.3-40 
Water.14-80 
Oats. 
13*6 
70-3 
3*3 
128 
100*00 100*0 
This table is in itself sufficient to show how a jaded horse 
may have the beans out of him, and it also explains why oats 
are more fattening than beans. 
Of the oily seeds we have several, the products of which 
are made use of as food or medicine. They are of two 
kinds; essential oils producing stimulating medicaments, 
and fixed oils producing fatty oily matter. 
Of the former we may instance the seeds of carraway, 
anise, carrot, coriander, &c., all of which belong to the 
natural order umbellifenB, the seeds of the whole of which 
are remarkable for the presence of little pouches between 
the ribs of the carpels, which are filled with oily matter thus 
described by Sir W. J. Hooker. Fruit of two single 
seeded pericarps or carpels, as they may be conveniently 
called, eventually separating, each with its style, and for a 
time suspended by a central, filiform, and generally bipartite 
column or axis. They are variously shaped, and variously 
marked with longitudinal 7'ibs or I'iclges. The number of 
these ribs upon each carpel is five. Within the coat of these 
carpels, generally in the interstices, are often longitudinal 
ducts or canals, replete with an oily or resinous substance, 
usually coloured, so that they are sometimes visible without 
dissection; these are called vittce.” 
One of the best seeds in which to examine these vittae 
or oil ducts is that of the parsnip, in which they are suffi¬ 
ciently large for dissection, and the removal of the pungent 
oil. 
Now what is remarkable about all these seeds is the varied 
forms which their simple parts have been made to assume; 
blit these are not more diverse than are the essential pro¬ 
ducts of their seeds; but different as is the flavour and re¬ 
lative power of these, they are all referable to the same 
type, and all would exert the same medicinal effects, varying, 
however, in degree or power. 
Of the fixed oils, we would refer to those of different nuts, 
as the hazel-nut, walnut, beechnut, &c., and to such seeds 
