Account of Sedge Wheat, Esfc. 



the species of crops, and the seed. It also proves the wonder- 

 ful advantage to be derived from studying the nature and ha- 

 bits of insects and other depredators. Here is a strong instance 

 of change being indispensable, even in the same genus of 

 grain. It would have availed nothing to have taken Mr. 

 Cooper's mode of selecting the best ears of the red chaff oeard- 

 ed wheat. None of that kind succeeded, or would have es- 

 caped the disease, or as I suspect, the ravage of the insect, 

 which may be so minute as to escape detection ; though our 

 correspondent, Mr. Evans, alleges he could find no insect in 

 his stunted wheat. The fact of the stunt always appearing in 

 the cow-pen'd or dunged ground, shews the probability that 

 the disease or its author, was resident in the straw or chaff 

 used in the pens. Insects are curiously inclined to feed on cer- 

 tain plants, in preference to others ; and their predilections are 

 so unaccountable, that they attack those of apparently different 

 natures. When more numerous than the favourite plants will 

 sustain ; they, 'tis true, devour all vegetation indiscriminately. 

 We know not to what cause to ascribe their common predilec- 

 tions. Last season the potato fly (lytta vitata) was in great, 

 plenty on my grounds. They nearly ruined a small patch 

 of potatoes I had planted, for experiment, in my garden, A 

 large bed of fine melons grew adjacent to the potatoes, and 

 %vere not touched by the fly. They passed over several 

 beds of other vegetables, and attacked the leaves of my scar- 

 citv roots, the first time I ever knew any insect or vermin 

 annoy them. Their ravages were really mortifying to me, 

 who am much attached to this root, and very desirous of bring- 

 it into general notice and culture. None of the common beets 

 were touched by the fly, though within their reach, on their 

 passage to the mangel wurtzel. And yet there is quite as much 

 affinity between the two kinds of beet, as there can be between 

 the red-bearded and the blue-straw wheats. I have frequently 

 recommended inquiries into the habits of insects ; and it would 

 be highly important to discover whether or not insects cause 

 the stunt. I know it will be difficult to establish any certain 



