n8 THE SCOTTISH NATURALIST 



Plies in House at Whittingehame. I have observed flies 

 coming into Whittingehame House every autumn for many years 

 past. Nearly all those about the size of a house fly (but I have 

 never identified the species) come in on the sunny days of 

 September when the nights begin to get cold. The length of the 

 house stands (roughly speaking) N.W. to S.E., and it is at the 

 S.E. end of the S.W. side that the flies chiefly come in, and much 

 more on the two upper storeys than on the ground floor. I 

 attribute this to their following the sunlight to the last possible 

 moment. There is at the W. and N.W. end of the house a group 

 of large trees, and as the sun goes down, the shadow of these trees 

 gradually rises over the house, so that the last place where there is 

 still sunlight is, as I mentioned, where the flies mostly go in. 

 That they come in by day is proved by the fact that if the windows 

 are kept shut all day and only opened after sunset, comparatively 

 few flies come in. Large numbers of a very small fly also come in, 

 but my belief is that they come in chiefly at night. The windows 

 of my room (which are the ones at the end of the house where the 

 large flies come in) are open all night, and on suitable nights I 

 notice a large number of flies on, or near, the windows in the 

 morning, of which there were no signs the day before. These 

 small flies come very much to any light place in the window. They 

 also come in chiefly in September. At the time of year when the 

 flies come into the house a quantity of Keating's insect powder is 

 dusted over the window ledges and the frames of the panes every 

 day, which kills or stupifies the flies on the windows, and those 

 thus disabled are destroyed. This gives a clear indication, therefore, 

 that numbers of them come in day after day. Alice Balfour, 

 Whittingehame. 



In October last Miss Balfour kindly sent a large number of 

 flies found on the windows of her house during the third week of 

 that month. I have worked carefully through the collections, 

 with the following result : of Limnophora sexnotata, Ztt., there are 

 several hundreds of females, but apparently no males; Pollenia 

 rudis, Fab., about 189 males and 379 females ; Pyrellia eriophthalma, 

 Mcq., over 200 males and about 300 females ; with a few odd 

 specimens of Sarcophaga carnaria, L. (4 females), small undeter- 

 mined Anthomyiidae (4 females), Muscina stabulans, Fin. (1 female), 

 Leptis Jringaria, L. (1 male), and Melanostoma mellinum, L. 

 (1 female). Percy H. Grimshaw. 



