QUEKETT MICKOSCOPICAL CLUB. 317 



electric lamp on behalf of Mr. E. B. Stringer, of Bromley, whicli 

 he had found suitable for microscopical use. Mr. Stringer, who 

 was unable to attend the Club's meetings, invited any member 

 interested in photomicrography to visit him. Members should 

 advise Mr. Stringer if they are at any time able to accept his 

 invitation. The Hon. Secretary said that he had had some corre- 

 spondence with Mr. H. Burrows, who was acting for the relatives 

 of the late John Ward, with regard to a quantity of unmounted 

 material that he had to dispose of. The Secretary had tried 

 several samples of the material and found it very good. 



Mr. Withycombe exhibited a larva of Taeniorhyncus Richardii, 

 which obtains its oxygen by piercing the roots of water plants with 

 its siphon, and also larvae of Anopheles flumheus and Finlaya 

 geniculatus, all from Epping Forest. Mr. N. E. Brown exhibited 

 two photographs of seed vessels of a species of the genus Mesembry- 

 anthemum, showing them open and closed, and described their 

 structure. They only open when wetted, and the seeds are some- 

 times washed out by the rain. The valves are forced open by 

 bands of hygrometric tissue, and the capsules open and close time 

 after time until they are rotten. In some cases Mr. Brown has 

 been unable to discover how the seeds are liberated, as the holes 

 seem too small to permit them to escape. 



The President then called on Dr. Tierney to give his lecture on 

 " Mosquito Investigation." Dr. Tierney said that there are over 

 1,000 species of mosquitoes, of which about thirty inhabit this 

 country, including three Anophelines, which are possible carriers 

 of malaria. The breeding habits of gnats do not vary greatly. 

 The males dance in a swarm, keeping always in the same place, 

 and the females go about singly. When a female approaches the 

 swarm the dance becomes a frenzy, the female darts into the 

 swarm, and after the nuptial flight takes a meal of blood. Egg- 

 laying then begins, the eggs hatch, and development into larva, 

 pupa, and imago follows. The eggs hatch in from two to four 

 days. Anopheline eggs are laid singly on the surface of the 

 water, and have floats which prevent them from sinking. The 

 eggs of Culicines and of Theobaldia are laid in rafts of from 2 to 

 400 eggs, which float. Some species will lay their eggs on a moist 

 surface, but no mosquito's eggs can resist desiccation. The larvae 

 of Culex are provided with siphons, by which they pierce the 

 surface film and obtain oxygen. Anopheles larvae have no 



