63 



pits that were left after their removal by the aid of the point of a 

 penknife. 



N^ola albula and K. centonalis also build cocoons of a similar 

 nature. N. centonalis feeds on leguminous plants, and when about 

 to pupate, at any rate in confinement, seeks some hard substance, 

 such as the twig of a shrub, or a drj^ grass stem, on which to build 

 its cocoon. r\\ albula in a wild state feeds chiefly on dewberry 

 {Iii(bus caniits), and no doubt the stems of that plant afford a suitable 

 position for the construction of its cocoon ; in confinement it takes 

 readily to raspberry, the stems of which it eagerly seeks for that 

 purpose. I have watched the construction of the cocoon, if not 

 continuously from beginning to end, at any rate at frequent intervals 

 during the process. On the evening of June 13th, a full-fed larva 

 was noticed resting on a piece of the stem of the foodplant, moving 

 its head from side to side in a manner suggesting that it was com- 

 mencing to construct its cocoon, and on a closer examination it was 

 seen that two narrow parallel lines of silk had been placed longi- 

 tudinally on the stem, one on either side of the larva ; these proved 

 to be the foundations for the side walls of the cocoon. From this 

 time the larva appeared never to leave the position it had taken up, 

 but resting between the two walls, to reach out its head, nibble a 

 fragment of bark from the adjacent part of the stem and weave it in 

 with the silk until the two parallel walls were of sufficient height. 

 This part of the process had been completed by the evening of the 

 14th, and on the morning of the 15th the ends and tops of the 

 walls had been closed up and the cocoon completed, the whole 

 process having occupied some thirty to thirty-six hours. (See Plate 

 v., figs. 1 and 2). 



The Spilosomas spin loose flimsy cocoons among rubbish in any 

 sheltered corner, mixing in the larval hairs, and often portions of 

 the rubbish, which materially adds to their concealment. S. iirticce 

 is a good example, especially when placed among moss, as is the 

 case in the specimens exhibited. On one occasion I found nine 

 cocoons of S. lubncipeda in the folds of a grey blanket that had been 

 left in a garden shed, the haiiy portions of the blanket being so 

 woven mto the cocoons as to make a practically exact colour match. 



Erioijaster lanestru makes a very special cocoon of a cylindrical 

 egg-ended shape composed of silk, in the outer layer of which a 

 brown pasty secretion is mixed, which makes it very hard and 

 capable of withstanding the wear and tear of the many years during 

 which the majority of a brood often remains in the pupal stage. 



Bowbyx qiierci'is constructs a cocoon on very similar lines, but it 

 is, of course, much larger and proportionately less tough. It is no 

 doubt the egg-like shape of the cocoons of these species that has 

 gained for the members of the group the popular name of " egger." 

 Cosmotriche [Odnnestis) potatoria spins a spindle-shaped cocoon 

 of tough, pale, dull yellow silk on a dry grass stem or thin twig of 

 a bush, and like that of Antkrocera tilipewhda, it is a most con- 



