Anniversary Address. 395 



where Galium horeale and Geranium sanguineum were 

 gathered. The others passed on to Haliden. In the mill- 

 pond there grew Nymphcea alba (planted no doubt), Alisma 

 plantago, Hippuris vulgaris, Menyanthes trifoliata, Myosotis 

 ccBspitosa, and such like aquatics. Silaus pratensis was seen 

 on the dryer ground. 



Campanula latifolia and Erysimum AlUaria were noticed 

 as we descended " Gledswood banks " to the Tweed. A short 

 seat here among the grass and ground ivy, brought up Acarus 

 autumnalis, the harvest bug, as the theme of conversation. 

 It is equally prevalent about Melrose as on the sea coast. It 

 is otherwise named the " Berry bug," from its occurrence in 

 gardens when the gooseberries ripen. It is no bug, but an 

 extremely minute mite, that burrows under the skin, causing 

 those small pimples that create so much uneasiness. In his 

 articles on the Aearides of Berwickshire, in the Club's 

 Transactions, Dr. Johnston has given a description and figure 

 of the mite. For my part, I have not examined it. Dr. John- 

 ston, however, failed to perceive that having only six legs, it 

 was an incomplete animal — a larva ; — eight limbs being the 

 complement of a full-grown mite ; and the problem is, which 

 is the mother mite that disperses abroad such a progeny of 

 invisible disturbers of the quietude of mankind, when disposed 

 to enjoy the solace of country retirement. My present opinion 

 is, that it may be traced to the species that I described as 

 Rhyncholophus haustor, in the " Ann. and Mag. Nat. Hist." 

 (ser. ii., vol vi., p. 117), which, however, may be identical 

 with the Acarus graminum of Schrank, "Gmelin, Syst. Nat." 

 viii., p. 2932 ; and for the reason, that it prevails to such an 

 extent on the grassy ledges at the sides of stone-walls in fields. 

 Now, this is also the metropolis of the harvest mite, and 

 whenever we walk along these grassy rims in Autumn, we 

 never fail to get our ancles quite blistered over with them; 

 or, if we chance to take shelter from a shower behind a fence, 

 the mites penetrate all parts of our clothing. Sometimes, in 

 hot weather, I have laid my coat upon the grass by the sea- 

 side, and found, on going home, that I had incurred a 



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