APPENDIX. LXXIII 



inferiority of the comparative quantity of sugar in the 

 summer crop, probably depends upon the agency of 

 light, which tends always in plants to convert sacchar- 

 ine matter into mucilage or starch. 



Amongst the soluble matters afforded by the 

 different grasses, that of the Elymus arenarius was re- 

 markable for the quantity of saccharine matter it con- 

 tained, amounting to more than one third of its weight. 

 The soluble matters from the different species of Fes- 

 tuca, in general afford more bitter extractive matter 

 than those from the different species of Poa. The 

 nutritive matter from the seed crop of the Poa com- 

 pressa was almost pure mucilage. The soluble mat- 

 ter of the seed crop of Phleum pratense, or meadow 

 cat's-tail, afforded more sugar than any of the Poa or 

 Festuca species. 



The soluble parts of the seed crop of the Holcus 

 mollis and Holcus lanatus contained no bitter extract, 

 and consisted entirely of mucilage and sugar. Those 

 of the Holcus odoratus afforded bitter extract, and a 

 peculiar substance having an acrid taste, more soluble 

 in alcohol than in water. All the soluble extracts of 

 those grasses that are most liked by cattle, have either 

 a saline or subacid taste ; that of the Holcus Ianatus 5 

 is similar in taste to gum arabic. Probably the Holcus 

 lanatus which is so common a grass in meadows, might 

 be made palatable to cattle by being sprinkled over 

 with salt. 



I have found no differences in the nutritive pro- 

 duce of the crops of the different grasses cut at the same 

 season, which would render it possible to establish a 



K 



