MIMICRY IN SILK- WORM MOTHS. xci 



form is curious in that, while the outlines indicate unmistakably a snake's 

 head, the colouration does not appear to have been modified to an equal 

 extent. Inhabits the Nearctic as well as the Oriental region. 



Fig. 5. — Samia cecropia (Linn.). — An American form showing a similar 

 aspect of a snake's head to the two last ; both eyes are represented. 



Fig. 6. — Saturnia simla (Westw.). — This form represents the snake's head 

 as it would appear to an observer somewhat below it. Subcostal black 

 spot representing eye, and pale subapical patch showing part of the snake's 

 head above the line of the mouth. An interesting form as the hind wings 

 appear to be somewhat modified, to represent an owl's head in certain 

 positions. (Plate No. II). 



Fig, 7. — Loepa hatinka (Westw.). — This form is interesting in that it shows 

 a marked tendency to snake imitation, even in a form in which the specific 

 colouration does not lend itself to mimicry of this kind. Yet here we 

 have the usual violet subapical j^atch referred to above, with a more or 

 less developed black spot between veins 6 and 7, and the other eye in- 

 dicated by a minute subapical costal spot. 



It is somewhat dilficult to imagine surroundings in which this form with 

 its unusually vivid colouration could be mistaken for a snake, unless, when 

 resting among similarly coloured leaves in deep shadow, it may resemble 

 one of the smaller bright green snakes. 



Another remarkable character in this family is the diaphanous spot in 

 the centre of each wing : in the hindwing these are, in many forms, much 

 enlarged and developed into conspicuous eye-like spots. These may be 

 intended to afford protection by presenting the appearance of an owl's 

 head when the moth is at rest amongst the leaves of a tree as suggested. 

 (Plate No. II.). These spots are most beautifully developed in this direc- 

 tion on the hind wings of Telea polyphemus, Cramer, an American form. 

 Of course, an owl's head would have an equally deterrent effect as that 

 of a snake on a small insectivorous bird. 



J. M. FAWCETT, Col., 



(late 5th Lancers). 



England, 1911. 



