38 HALF-AN-HOUR 



scales of fish (Micro. Die. sub-lite, and in the bony epicarp of many 

 fruits, as may be seen on examining a cherry or plum stone, or the 

 seed of a currant, blackberry, or hawthorn-berry. When J. Quekett 

 first lighted on such structure in the vegetable-ivory nut, he was 

 much puzzled at the close juxtaposition of fibre-cells running both 

 longitudinally and transversely to the axis of the section (Lectures 

 on Histology, Vol. I., p. 64). Further examination, especially in 

 the early stages of its development, would have shown this acute 

 and tireless investigator the real explanation of the fact. 



Development of Culex Pipiens (Plate 4, Figs, i — 4). — The 

 Society is deeply indebted to the contributor of this slide. Few 

 pupae are so well adapted to display the development of the 

 imago as Culex on account of the transparency of the covering 

 membrane. A full description is given in the explanation accom- 

 panying the plate. 



Antennae of Diptera (Plates 5, 6, 7). — Sixteen examples of 

 Antennae show well what may be done by thoughtful care and 

 patience. Members will do well to see what they can do after 

 this style, and even if the result should be unsatisfactory at first, 

 time and patience will give the requisite skill in the end. May I 

 say it is of no use wishing without pains are taken to bring about 

 the results wished for. There is a considerable resemblance be- 

 tween Fig. 14 (Plate 7), and those of Miisca vomitoria, even to 

 the strong spine proceeding from the dorsum of the second joint ; 

 they are evidently congeneric. 



Eristalis teiiax is the great Drone-fly, the antennae of which 

 may be compared with Fig. 13 (Plate 7.) Chrysops caciitiens (Fig. 

 5, Plate 5) is the Gad-fly. The peculiar tapering antennae oi E^npis 

 livida (Fig. 6, Plate 5), is worthy of notice. 



It may indeed be said of the Diptera, "Their name is Legion;" 

 but if the fine typical examples of parts, as mouths, antennae, wings, 

 limbs, which pass round, be carefully studied, and Notes and 

 Drawings 7nade by our members^ a clue will in time be obtained 

 through the labyrinth of forms. These would illustrate admirably 

 what I wish so to impress, the absolute necessity of systematic 

 work, and of doing thoroughly whatever is taken up. 



Aleurodes Chelidonii.— This insect is not Lepidopterous, as 

 some suppose, but truly Homopterous, as may be readily ascer- 

 tained by observing the various stages of development, and the 

 parts of the mouth in the mature insect. I do not know how the 

 name Chelidonii came to be conferred on it ; it is true, an occa- 

 sional specimen may now and then be met with on the Great 

 Celandine, but its natural habitat is on the under side of leaves of 



