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On Stenopteryx hirundinis, L., a 'parasite of the Swallow 

 observed at Lauder. By John Turnbull and Wm. 

 Grant Guthrie. 



To THE meeting of the Club, held at Newcastleton on the 

 31st July 1895, a glass tube, containing insects, was sent 

 for exhibition with the following note. 



Insects found at Lauder. 



On Saturday afternoon, 27th July 1895, during a down- 

 pour of rain, a young Swallow flew in at the open window, 

 and sat for a few minutes on the middle bar. I took it 

 in my hands and carried it to the open air, and let it fly 

 away. I found the insects (enclosed in the tube) running on 

 my hands ; they must have come off the Swallow. 



I put them under the glass of my watch, the better to 

 observe them. When first enclosed they were very active, 

 and ran easily on the smooth dial. 



The body and legs were semi-transparent, with short stiff 

 bristles all over them ; the abdomen large in proportion to 

 the rest of the body, two lobed thus (4;, and of a light 

 green colour. The feet are articulated, and have black 

 hooked claws. There are two projections on the back like 

 aborted wings, or wings folded lengthwise. 



On Sunday morning an oval, brown eg^ had been laid by 

 one of them, and on Monday morning another white one. 

 All were dead on Monday evening, no doubt from want 

 of food. 



JOHN TURNBULL, 



Gas Works, Lauder. 



Note with Reference to the above. 



The insects enclosed in the glass tube are true flies, 

 Stenopteryx hirundinis (Leach) ; Dipterous parasites on the 

 Swallow. 



The female fly is said to produce only one or, at most, 

 two eggs at a time ; these are hatched in the body of their 

 parent, where the larv£e remain till full fed, assuming the 

 pupal stage immediately on being extruded. The oval, 

 brown Qg^ mentioned above is therefore really a pupa ; the 



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