28 CUIUOSITIES OF KNTOMOI.OGY. 



marking the species, there are rows of cup-like sockets into 

 which each tiny scale is fitted securely for the insect's flight, 

 but Avhich Avill not bear the coarse touch of human fingers. 

 These scales, invisible to the naked eye, are composed of three 

 distinct lamina?, two external and coloured, tlie inner one a 

 highly polished colourless membrane, which reflects the light 

 and increases the brilliancy of each scale. The wing of this 

 little Cemiostoma, shining with the silvery grey mass of 

 microscopic feathers, has a large black spot with violet eye, 

 and streaks of purest white, and deepest black, radiating off 

 into the long silken fringe that is so remarkably beautiful in 

 all these moths. The egg, strangely large for the size of the 

 moth, is laid on the under side of a leaf, and the larva, as soon 

 as hatched, bores through the cuticle and eats away a cavern 

 in the parenchyma or cellular tissue, which daily spreads into 

 a large blotch, brown at first but afteruards white, with 

 markings of black in half circles, which is the excrement of 

 the worm as it works from side to side. When full fed it 

 comes out at the upper side of the leaf, and s])ins a pretty 

 white cocoon, leaving a slit at one end, through which it rejects 

 the cast-off skin when assuming the pupa state, and by which 

 the little moth eventually comes forth. 



Cemiostoma laburnella (Fig 2) is a delicate white motii, 

 with violet pupil on its wings, and should be mounted on a 

 blue disc, for then the dark radiating streaks in the cilia will 

 be more distinctly seen. 



There is another moth, Cemiostoma spartifolia, which mines 

 the tioig, not the leaf, of the common broom, and so like the 

 Lahurm'lla that only a practised eye can discern the slightest 

 difference, although there is invariably one slight variation 

 marking its individuality, for the wing of C. laburnella has 

 three parallel lines passing from the second yellow dot through 

 the cilia, while the wing of C. spartifolia has three concerying 

 strokes from the same dot. Two broods in the year spoil our 

 laburnum leaves in appearance, but not in reality ; for 

 although the little insect feeds upon the pulp of the leaf, the 

 veins or channels of the sap are not injured, and the 

 tree itself does not suffer in vitalitv, at least to any oreat 



