DIMORPHA VERSICOLORA. 253 



green, slightly inclining to yellowish in the lightest, and to bluish 

 in the deepest, portions and in the dorsal line ; below the yellow 

 stripes, which are bordered above with green, the ground colour 

 of the sides is of a very deep and rich full green, increased in depth 

 by the clcse irroration of minute black dots, and relieved by the 

 white oval spiracles delicately outlined with black ; ' in front of 

 these comes a thin line of quiet ochreous-greenish, as though a 

 continuation of the slanting stripe from the preceding segment, more 

 noticeable on approaching the ventral prolegs, which, like the base 

 of the anal pair, are bright crimson ; the whitish-yellow stripe on the 

 side of the eleventh segment continues downward beneath the 

 spiracle on the twelfth. From the top of the white, horn-like 

 hump, which is divided by a thin line of black, a whitish stripe 

 descends on either side in a slight backward curve, and the anal 

 flap is margined with yellowish ; the anterior legs are pale green, 

 sometimes tipped with red, and with a black hook. When fullfed 

 all the green colours of the larva change to brown, and it becomes 

 restless until it finds the moss and leaves needful for its retirement 

 and the construction of its cocoon (Buckler, Larvae Brit. Butis., &c, 

 vol. iii., pp, 62 — 65). Two beautiful figures of the larva are also given 

 by Buckler (Joe. eif., pi. li., figures 3, 3^). 



Change of colour in fullfed larva. — Before pupating, all 

 the green parts of the larva change to red-brown as is the case with 

 many of the Sphingid larvae. At this time it leaves the tree on 

 which it has fed in order to find a suitable place for pupation. 

 There can be no doubt that this change of colour is highly useful 

 for protective purposes. 



Pupation. — The larvae spin up among the roots of low plants, 

 just below or upon the surface of the ground near the bushes upon 

 which the larvae have fed (Reid) ; among moss, leaves, or such other 

 debris as may happen to be at hand, usually at the latter end of 

 June or early in July (Gascoyne) ; fastened up in dead leaves about 

 the roots of trees (Merrin) ; just below the surface of the ground 

 (Riihl). In confinement, place the fullfed larvae upon sandy earth, 

 mixed with cocoa-nut fibre, and they will spin up readily and keep 

 safely (Bernard-Smith). 



Cocoon. — The cocoon is made of tough brown silk, in the outer part 

 of which, moss, leaves, &c, are interwoven; it narrows off somewhat 

 at each end. Looked at against the light it is found to consist of a 

 loose network, and the pupa may be seen inside ; at one end the 

 structure is looser in order to facilitate the escape of the imago ; 

 the inside of the cocoon is smooth and shiny, covered with a 

 salivary-looking varnish, making the structure probably waterproof 

 (Tutt). Buckler says that the cocoon varies in length from 1" 

 4'" to 1" 7'", and is of long elliptical shape, being from *6 ins. to '8 

 ins. in width ; it is composed of an open-worked reticulation of 

 coarse black or black-brown silk threads, with round or broad 

 oval interstices ; the fabric is extremely strong, tough and elastic, 

 covered externally with moss and birch leaves firmly adherent. 

 Bacot says that cocoons containing $ pupae average i*2in. in length 

 and "5m. in width, those containing $ pupae i*8in. in length and 

 •7m. in width ; usually spun in an almost upright position, although 

 others' are almost horizontal \ formed of an open network of strong, 



