1915.1 269 



the surface-film of the wet mud or water. During the resting-stage prior to 

 pupation they do not seem to use the siphons, but lie buried several inches deep 

 for weeks or even months. 



Pixpation occurs an inch or more below the siu-face, the pupa standing up- 

 right in the mud, head vip wards. As soon as the pupal case has hardened, the 

 pupa works its way upwards by means of its spines, till the head is just below 

 the surface. In fine weather the imagines of all species almost invariably 

 emerge between noon and 3 p.m., but they are less regular in dull or rainy 

 weather. The process is very similar in the different genera, the pupal head 

 splitting along the mid-dorsal line. The abdomen is at first greatly elongated. 

 The wings rapidly assume their full development and the insect is soon capable 

 of flight. 



Attempts were made to keep the adults alive in captivity. If the walls of 

 the cage are at all resistant, the creatures knock themselves about and swiftly 

 die. But in cages with loose net-walls they survived much longer, in some 

 cases two or three weeks. It was not easy to induce the captives to suck blood. 

 In some species of Tahanus both sexes fed greedily on honey and water. This 

 attraction to sweet substances, whether honey or the honey-dew of Homoptera, 

 has been previously noticed. 



Structural differentiating characters are provided by the "aster," or group 

 of hooks on the terminal segment of the pvipa, and in the larvae to some extent 

 by areas of pigmented hairs (in which are entangled small foreign bodies) on 

 the last segment. 



*^* A CoRBECTiON. — Mr. W. E. Thompson has called my attention to an 

 error in my abstract of one of his papers, at the bottom of p. 222 of the present 

 volume. It was stated that Tachinid larvae were found in *' a Noctuid cater- 

 pillar {Hamevialis virginiana)." This should have read "a Noctuid caterpillar 

 on Hamamelis virginiana." H. virginiana is a bush, the witch-hazel, and the 

 name of the genus is Hamamelis, not Hamemalis. The species of caterpillar 

 was undetermined. 



Societies. 



The South London Entomological and Natural History Society : 

 Thursday, July 8th, 1915.— Mr. B. H. Smith, B.A., F.E.S., President, in the 

 Chair. 



Mr. G. B. Pearson, Eussell Square, W., was elected a member. 



There was a special exhibition of Malacosoma neustria, M. castrensis, and 

 Cosmotriche potatoria by Messrs. B. Adkin, E,. Adkin, S. Edwards, A. E. Gibbs, 

 Luis, Sperring, and Brooks, which included series of numerous local races and 

 many aberrations. Mr. B. Adkin then read a series of notes on the variation 

 attainable in the three species. Mr. B. S. Williams exhibited a bred series of 

 Bupalus piniaria from Leith Hill. Mi-. "West (Ashtead), examples of Triaena 

 psi and T. tridens. and asked if members could jjoint out definite markings 

 whereby the imagines could be correctly distinguished. — Hy. J. Turner, Hon. 

 Secretary. 



