28 CORN AND GRASS. 



windows, has often been reported, in a few instances from English and 

 Irish localities, but chiefly from Scotland. As the infestation had 

 been carefully identified, and the presence of these, literally, " heaps" 

 of Mites, though very unsightly, is really almost or quite harmless, it 

 would have seemed unnecessary to bring the matter forward again, had 

 it not been that amongst this autumn's observations there has been 

 one on such a large scale, that the enquirer had been seriously advised 

 to burn his infested stacks. 



This enquiry was forwarded on to me per favour of tbe Editor of 

 the ' Scottish Farmer,' and will be found in tbe number for Oct. 13th 

 (1894) of that Journal, p. 813, in the following words : — " My hay is 

 all covered with Mites, and on application to local experts, I am 

 advised that the only remedy is to burn the stacks. Can you suggest 

 anything less summary?" To this, of course, I replied that on no 

 account would I advise such destruction ; but as it appears the nature 

 of this infestation is not sufficiently known for such a course to be 

 possible, it may be useful to give a digest of what is known about it 

 up to the present time. 



These Mites (which in the absence of any popular name it is 

 convenient to describe as Hay Mites) are scientifically the Tyroglyphus 

 longior. They are exceedingly like the " Common Cheese Mite," the 

 Tyroglyphus siro, and, like it, are at times to be found in cheese ; but 

 they are larger than the Cheese Mite, longer in proportion, have much 

 longer hairs, and are more active. The rapidity of movement, and 

 the length of the hairs of the adult specimens, I have found very 

 noticeable in microscopic observation. The figure (p. 27) gives a very 

 good idea of the appearance, much magnified, and also shows the 

 single claw which (with the sucker also), at the end of the leg, is 

 characteristic of the sub-genus Tyroglyphus. 



Like most of the order of Acarina, or " Mites," to which they 

 belong, they are hatched from eggs, and (also like most of this order) 

 in their early stage have three pairs of legs, and, when mature, four 

 pairs. When seen in small numbers, and without magnifying powers, 

 they are indistinguishable from the common Cheese Mite ; but when 

 fallen down in the vast numbers in which they are from time to time 

 observed in autumn, they are like masses of live, slightly moving, 

 greyish dust. They occur as dropping from haystacks, or from lofts 

 where hay is stored, in quantities described as shovelfuls, or as lying 

 an inch or more deep round stacks, or the hay itself being alive with 

 them. In one report sent me from Swaffham, Norfolk, on the 25th of 

 August, 1892, the Mites were described as having been dropping on 

 the ground in vast quantities for several days from a stack of that 

 year's hay, and that they lay in masses of many quarts heaped up 

 upon the ground, A report from another correspondent from near 



