THE BIOGENETIC LAW 



179 



longitudinal striping is effective as a protection in the case of young 

 caterpillars, supposing, that is, that they live in or on the grass (Fig. 1 16). 

 Let us consider the ontogeny of these different forms of markings, 

 beginning with the eye-spots. It appears that these develop from 

 a sub-dorsal stripe, which appears in the young caterpillar in the 

 second stage of its life, and from it, in the course of the further 

 development, two pairs of large eye-spots are formed. Even in the 



Fig. 4 (repeated). Full-grown caterpillar of the Elephant Hawk-moth, 

 Chcerocampa elpenor, in its 'terrifying attitude.' 



young caterpillar, scarcely one centimetre in length (Fig. 116), it can 

 be observed that the fine, white sub-dorsal line takes a slight curve 

 upwards on the fourth and fifth segments (C), and on the lower edge 

 of these curves a black line is laid down (7)). This is then continued 

 to the upper side (E), and encloses the piece of the sub-dorsal stripe 

 (i^and G), and thus there arises a white-centred, black-framed spot 

 which only requires to grow and to differentiate a blackish shadow- 



B 



r 



Fig. 8 (repeated). Caterpillars of the Buckthorn Hawk-moth, Beilephila 

 hippopha'fis. A, Stage III. B, Stage V. r, annular sj^ots. 



centre, the pupil {G), to give the impression of a large eye. This 

 occurs as the caterpillar goes on growing, and after the fourth moult 

 or ecdysis the eyes have already some effect, as the animal is six centi- 

 metres in length, but they become even more perfect in the fifth and 

 last stage. During this development of the eye-spot the sub-dorsal 

 stripe disappears completely from the greater part of the caterpillar, 

 persisting only on the first three segments (Fig. 116, B-F). 



N 2 



