HYLES EUPHORBIA. 213 



a diminutive plant, while large robust plants close at hand had 

 none on them (Mathew). The eggs are laid at the top of the plants 

 among the soft budding leaves (Melhuish), light green in colour 

 and usually eight or nine near together (Johnson). The eggs when 

 laid, are covered with an adhesive gummy substance, by means 

 of which the 2 fastens them to the small leaves of the spurge 

 (Raddon). In confinement the eggs are laid at the base of the 

 leaves of Euphorbia cyparissias, in small clusters, composed some- 

 times of as many as seven, the single eggs being placed near together, 

 but never touching, and seldom at the point, of the leaf, but generally 

 near the end of a twif, where young shoots are in close proximity 

 (Weismann). 



Ovum. — Bright pea-green in colour, semi-transparent in appear- 

 ance ; nearly spherical in outline; length rimm,, width iram.; 

 one end very slightly broader than the opposite ; surface smooth, 

 covered, however, by a small and faintly marked cellular pitting 

 or faceting. [Eggs received from Dr. Chapman.] (Bacot). Green, very 

 small in proportion to the size of the moth, smaller than those of Mimas 

 tiliae (Bartel). The eggs much resemble those of Eumorpha elpenor, 

 being spheroidal in form, but rather smaller, and of a somewhat darker 

 green. During the embryonic development the eggs become coloured, 

 first yellow, then partly blackish, and, finally, completely black 

 (Weismann). 



Habits of larva. — The newly-hatched larva does not eat the 

 eggshell (Sich). When quite young, the larvae are always found 

 among the soft budding leaves at the top of the plant, working 

 their way down, eating leaves, stalk, flowers, and seeds, all except 

 the central stem, till they reach the ground when they run off in 

 search of fresh food, leaving behind them a broad trail in the sand in 

 which each foot's tread may be distinctly traced. Stripped plants 

 are a sign that the larvae are gone but they will be found not far off; 

 if leaves be withered they will be underground, but, wherever there 

 is a green-looking bed of Euphorbia, you are sure of a score or two. 

 They prefer the seedvessels and young stalks as these contain most 

 of that milky juice which is their great delight, and, if a twig be 

 broken, they will fasten on the broken end and lick up the milk as 

 it oozes out. The seedvessels they take between their front legs, 

 and, raising themselves into the Sphinx posture, gnaw away at one 

 till it is demolished, just like a monkey with an apple, their feet 

 close before their mouths ; if interrupted when feeding they turn 

 round with the greatest fury and spit out a quantity of green liquid 

 of an acid and disagreeable smell, similar to that of the spurge-milk 

 only worse. When a larva after rambling about finds a fresh plant 

 to its taste it sets to work at once upon the bottom leaves, merely 

 raising up its head from the ground, and devours all within its 

 reach, before proceeding to climb the stem ; these bottom leaves 

 are, of course, very inferior, but were the large larvae, who are old 

 enough to travel, to mount up to the top at once and eat all the 

 tender shoots, all the little larvae just out of their eggs would be 

 starved. A larva never turns — it goes up or down according to 

 circumstances, but only one way; they must swallow large quantities 

 of sand, for, however sandy a leaf may be, if it be fresh they never 

 reject it on that account. Trails and frass are proof positive of the 



