THE OVUM OR EGG. 13 



pocket, in the soft cellular tissue of the leaf. Sufficient examples have 

 been given to illustrate the almost endless variety that exists in the 

 egg-laying habit among Lepidoptera. 



The eggs of Lepidoptera are usually laid upon or near the food- 

 plant of the larva, but this is not always the case. Triphacna pronuba 

 frequently chooses a piece of wire (in a fence), or cord hanging loosely 

 in a garden, for the purpose. Riding reports batches of eggs of this 

 species in two successive years (1895, 1896), on the meshes of a lawn 

 tennis net. Ckrytophannu phlaeaa and Polyommatiis icarus frequently 

 deposit eggs on objects adjacent to the food-plant, so also, more rarely, 

 do Pararye eyeria, P. nreyaera and Pieris napi. Many ground feeding 

 Noctuids lay on the stems of dead plants, leaves of trees, etc., and so 

 also do Arctia caia, Spilosoma menthastri, and many other Arctiids. 

 Riding records the finding of eggs of Macrothylacia (Lasiocampa) 

 rubi on the trunk of a pine, at a height of nearly six feet from the 

 ground, whilst a couple of the linear leaves of a Weymouth pine were 

 girdled by 70 or 80 rows (10 eggs in each) of the eggs of a Noctuid 

 moth, which turned out to be those of Tiipliaena pronuba. Acidalia 

 perochraria appears to follow the habit of the Hepialids, Melanaryia 

 yalatea, Pararye achine, etc., and to sprinkle her eggs on the ground. 



In the case of eggs laid naturally upon the leaves of deciduous 

 trees or annual herbaceous plants, the egg-stage is usually a short one. 

 On the other hand, when the eggs are laid upon the stems, leaf- 

 buds, etc., of plants, the egg-stage may last a considerable time. The 

 former is the method usually adopted by Geonaetrids, Noctuids, 

 Sphingids and their close allies, although the Xanthids, Catocalids, 

 Ennomids, etc., will occur to the mind at once as exceptions. It is 

 remarkable that those eggs laid on leaves, and on grass stems are, as 

 a rule, of a white, yellow, or greenish hue, whilst those on the twigs of 

 bushes and trees are of a dirty white or grey, and frequently assume 

 a purplish or red-brown tint, e.y., Theda w-albuin, Ennomos autumnaria, 

 Enilramis versicolor, Tiliacea aurayo, Cirrhoedia jcerampelina, DicJumia 

 aprilina, etc., and it will be found, as a general rule, that those species 

 which hybernate in the egg-state, have eggs, which rapidly change to 

 some dark hue that corresponds well with the colour of the stem or 

 twig on which the egg is frequently deposited. Those that are 

 scattered on the ground are usually of a dirt-colour, or have a pearly 

 appearance ; in fact, with a few apparent exceptions, the colour of 

 lepidopterous eggs rapidly becomes such as to make them difficult of 

 detection by the various predaceous creatures that prey upon them. 



The peculiar resemblance of a rouleau of the eggs of lodis vernaria 

 to a broken tendril of Clematis mtalba, the plant on which the eggs 

 are laid, has already been noticed. The easy way in which Tephrosia 

 bistortata, Bistonhirtaria. Amplddasys xtrataria (prodromaria), Orrhodia 

 vaccinii, Dicycla oo, and their allies, pack their eggs deep into the bark 

 crannies out of sight, attracts attention at once, because of the protection 

 afforded. Anitoptetyx aescularia, Krioyaster lancstrift, Porthesia similis, 

 P^chrysovrhoea and Porthetria dispar cover their eggs thickly with silky 

 hairs from the extremity of the abdomen. Leucoma salicis covers its 

 eggs with a substance that has a salivary-looking appearance, but 

 which is quite solidified, and various other devices have been developed 

 by individual species for the protection of their eggs, and, as a rule, 

 it appears probable that less destruction takes place in this, than in 



