QUEKETT MICROSCOPICAL CLUB. 391 



nominations would be received to fill the vacancies on the com- 

 mittee caused by the retirement of the four senior members. 



Mr. J. Milton Ofiord, F.R.M.S., then gave a lantern demonstra- 

 tion on Insects' Eggs. Mr. Offord apologised for giving an address 

 to the Club which contained nothing new, but he thought that the 

 beauty of the eggs was sufficient excuse for his bringing the subject 

 before the members. He drew attention to the remarkable 

 instinct which guides the insects in selecting a suitable place to 

 deposit their eggs, so that the young larva on emerging finds 

 suitable food close at hand. The emergence from the egg is> 

 sometimes a matter of considerable difficulty owing to the young 

 larva becoming entangled in the membrane with which the egg; 

 is lined. Some insects, earwigs for instance, sit on their eggs, but 

 the speaker was not able to explain why this is done. The eggs 

 of Lepidoptera are generally glued to the leaves of the food plant, 

 those of saw-ffies are laid in cuts or cre^dces of the bark, while 

 the eggs of the bot-fly are laid on the hair of horses so that they 

 may be transferred to the animals' mouths when they lick them- 

 selves, and so reach their stomachs where the development i& 

 continued. 



A series of lantern, slides of eggs of various lepidoptera, diptera 

 and avian parasites was then shown on the screen, and although, 

 the beautiful iridescence was in some cases lost, the variety of 

 form was well exhibited. The photographs were taken with, 

 either a Zeiss Planar or a Zeiss 35-mm. projection lens. . The 

 first of the series were the eggs of butterffies, and a great variety^ 

 of shape and markings was shown. The Cabbage White and the- 

 Brimstone lay long eggs rather pointed at one end ; they are 

 longitudinally ribbed, and the ribs are connected by crossbars- 

 which in the Brimstone's egg are dotted. The eggs of the 

 Chequered Skipper bear similar markings, but are shaped like an 

 orange. Mr. Offord suggested that this ribbing might be for the 

 sake of economy of material, to get as much strength as possible 

 with the amount of material used. The next egg shown, that oi 

 the Silver-studded Blue, was quite different ; its surface was. 

 covered with small tubercles, and its appearance greatly resembled 

 that of the seed of Silene. The eggs of the small Copper again 

 showed a shell apparently strengthened by projecting ridges^ 

 but in this case the surface was honeycombed. Mr. Offord 

 then showed some moths' eggs : those of the Swallow-tail were 



