HORTUS GttAMINEUS WOBURNENSIS. 41 



But besides this agreement of external structure, grasses are 

 distinguished from other natural orders of plants by this property, 

 that every part of the plant becomes food for the larger aud more 

 valuable domestic animals. Other natural orders of plants afford 

 only the fruit, or seed, or perhaps the root ; others again are poi- 

 sonous : it follows, that the properties of plants, when distinctly 

 known, may be included with advantage in their natural chajiacters 

 of distinction. 



All the species which compose this family, may also be distin- 

 guished from each other by the difference in the qualities of the 

 nutritive matter which each affords. Those species which have 

 the greatest affinity to each other in external form, likewise con- 

 tain nutritive matters, that differ less from each other in their sen- 

 sible qualities or composition, than those of the species which are 

 more dissimilar in their external figure. However circumscribed 

 the knowledge of this connexion may be, which seems to exist 

 between tlie external forms and nutritive products of grasses, still, 

 if certain external characters should be found to indicate peculiar 

 nutritive qualities, the botanical description of any species of grass 

 would not only convey a knowledge of its external form, but like- 

 wise an idea of its value, as an article of food. That this would be 

 productive of much practical utility, can hardly be doubted; and 

 the following particulars, stated from the results of attentive 

 observation, and numerous comparisons made in the course of the 

 experiments, and which gave occasion for the above remarks, may 

 at least shew, that the subject is worthy of further investigation. 



1st, Grasses which have culms with swoln joints, leaves thick 

 and succulent, and flowers with downy husks, contain greater pro- 

 portions of sugar and mucilage. 



2d, When this structure is of a light glaucous colour, the 

 sugar is generally in excess. 



3d, Grasses which have culms with small joints, flowers 

 pointed, collected into a spike, or spike-like panicle; leaves thin, 

 flat, rough, and of a light green colour ; contain a greater propor- 

 tion of extractive matter. 



4th, Grasses which have culms furnished with numerous joints, 

 leaves smooth and succulent, flowers in a spike or close panicle, 

 florets blunt and large, contain most gluten and mucilage. 



5th, When this structure is of a glaucous colour, and the florets 

 woolly, sugar is in the next proportion to mucilage, (No. 2.) 



6th, Grasses which have their flowers in a panicle, florets 



