124 NEW ZEALAND MACRO-LEPIDOPTERA. 



larvae are extremely active, and immediately after hatching leave the old case, and roam 

 in all directions over the tree, letting themselves down from branch to branch by 

 silken threads. They carry the posterior portion of their body elevated in the air, 

 walking whilst doing so by means of their strong thoracic legs. 



The food-plants of this species are numerous. The following are a few of them : 

 Manuka (Leptospermuiii scuparium and ericoides, Cupressiis macrocarpa, Pinus insignia), 

 and various species of willow, &c. These, it will be observed, include several introduced 

 trees. In fact, the insect is a very general feeder. About three days after leaving the 

 egg, the little caterpillar constructs a minute, conical-shaped, silken case, which it carries 

 almost in an upright position on its posterior segments. Later on in life this case 

 becomes too heavy to be held vertically, and is afterwards dragged along by the larva, 

 and often allowed to hang downwards. The case has two apertures a large one in 

 front, through which the head of the larva is projected, and a smaller one at the posterior 

 extremity, which allows the pellets of excrement to fall out of the case, as soon as they 

 are evacuated. 



Owing to the apterous and completely helpless condition of the female imago, it 

 is evident that the dispersal of this insect must take place in the larval state. 

 Distribution is of course quite impossible without a female being transported in some 

 way, and from observations made on a good many larva? of various ages, I am disposed 

 to think that the migration of this insect to new localities takes place at an early age, 

 possibly soon after its emergence from the egg. On this account I think that the 

 occurrence of the moth in both North and South Islands is of great interest, as it would 

 seem to indicate the existence of some connection between the two islands, at a period not 

 sufficiently remote to have allowed any appreciable modification to take place in the 

 insect's structure and habits. At the same time, it should be borne in mind, that the 

 protection afforded the larva by its case, and its ability to feed on so many different 

 plants, may have rendered any modification unnecessary for the preservation of the 

 species during recent times. The length of the full-grown caterpillar is about 1 inch. 

 The head is dull yellow speckled with black. The first three segments are very hard, 

 dark brown, with numerous white markings. The remaining segments are considerably 

 thickened near the middle of the insect, rudimentary prolegs being present on the seventh, 

 eighth, ninth, and tenth segments of the larva. The anal prolegs are very strong, and are 

 furnished with numerous sharp booklets, which retain the larva very firmly in its case. As 

 the caterpillar grows, it increases the length of its domicile from the anterior, causing it 

 gradually to assume a more tubular form, tapering towards the posterior aperture, which is 

 enlarged from time to time. The outside is covered with numerous fragmentary leaves 

 and twigs of various sizes, placed longitudinally on the case, and, frequently, near the 

 anterior aperture the materials, owing to their recent selection, are fresh and green. The 

 interior is lined with soft, smooth silk of a light brown colour, the thickness of the whole 

 fabric being about the same as that of an ordinary kid glove, and so strong that it is 

 impossible to tear it, or indeed to cut it, except with sharp instruments. The size of the 

 case, when the caterpillar is mature, varies considerably, ranging from '2 to 3 inches or 

 more in length, and about J inch in diameter, the widest portion being a little behind the 

 anterior aperture. 



During the day the larva closes the entrance, and spins a loop of very strong silk 



