Length.Breadth.
Barley0·103–0·224mm.0·012–0·014mm.
Rye0·086–0·3450·012–0·016
Wheat0·152–0·4490·018–0·024
Oats0·186–0·4480·012–0·017

Another distinctive feature of straw-fibre is the presence in it of a number of oval cells, derived from the pithy matter attached to the inside of the stem. These are clearly shown at b (Fig. 13), which represents the general appearance of straw pulp.

FIG. 13.

General chemical characteristics.—Both ligno-cellulose and pecto-cellulose.

The following are the results of analyses of straws (Hugo Müller):— {59}

Winter Wheat.Winter Rye.
Cellulose46·6047·69
Fat and wax 1·49 1·93
Aqueous extract 8·07 0·05
Non-cellulose or lignin28·4926·75
Water 9·8511·38
Ash 5·50 3·20

BAMBOO AND SUGAR CANE.

From the close botanical relationship of these products to the stems of the gramineæ of our own climate, their microscopic features are, as might be expected, similar to those of straw. The similarity is further shown by the chemical composition (Hugo Müller):—

Air-dried
Cellulose50·13
Fat and wax  ·78
Aqueous extract10·56
Lignin and pectous substances24·84
Water 8·56
Ash 5·13