MALACOSOMA CASTRENSIS. 537 



when pupating, otherwise they spin the cocoons on one another, and 

 thus many are prevented from escaping when the imaginal stage has 

 been reached. Newman observes that the web constructed by the 

 young larva? is thinner and less opaque than that of 21. neustria, 

 and is generally placed very near the ground. Linne noticed 

 their gregarious habits, and says : " Polyphaga, pascitur sub 

 tela, gregaria, migratque sa?pius novo tentorio ; ova, more pra?- 

 cedentis, in annulos conferta circum ramulos. Ha?c frequens in 

 Suecia, duplici colore occurrit, eadem tamen, diversaa praecedenti 

 (neustria), cum ilia arborea, haec terrestris " (S;/st. Nat., xiith ed., 

 p. 818). After they leave the web they do not wander far, so that 

 when a full-fed larva is found others are sure to be close by 

 (J. J. Walker). Jones observes that on June 30th, 1871, the larva? 

 were in hundreds on Higham marshes, and were not at all confined to 

 the sea-wall, but occurred for a mile inland ; they were equally com- 

 mon on the Gravesend marshes near the sea-wall. He noticed that at 

 10 a.m. the larva? occurred only sparingly, but as noon approached 

 they became more abundant, crawling up from their retreats to sun 

 themselves upon the branches of their food. After 1 p.m. they again 

 became much scarcer, retiring to the roots of their food-plant. In 

 confinement the larva? should be put in the sun. Whittle notes that 

 the food-plants and the larva? themselves must often be submerged. 

 He says that the larva? love the sunshine, but the evening is the great 

 feeding-time, and then they may be found freely enough on almost any- 

 thing that grows on the salt marshes. Wright observes that the half- 

 grown larva? rest side by side, in masses, on the sea-plantain and other 

 plants, all with their heads towards the sun, basking in the warmth, 

 and are so sensitive that, on the least disturbance, or on the approach of 

 an intruder, every head would instantly be raised and thrown back. 

 James says that in June, 1881, the larva? were in large numbers, feed- 

 ing on dried seaweed on the seashore, at Bawdsey Ferry, near 

 Felixstowe, and were distributed over a long ridge of the seaweed that 

 had been washed up by some extraordinary high tide, at some yards 

 above high- water mark. Two of the larva? found had spun up in the 

 mouths of large whelk-shells, and the specimens bred from these are 

 still in his collection. Ingall notes that on July 5th, 1856, the larvae 

 were in immense abundance near Queenborough, chiefly full-fed. 

 They were crawling about in such profusion that he could scarcely 

 walk without treading upon them. Lambert writes that the larva? 

 may be taken from July 15th to the end of the month, are rarely to be 

 found except when the sun is shining and the weather warm, when 

 they may be seen feeding on the young tops and unexpanded blossoms of 

 Artemisia maritima ; he notices that the larva? have a habit when feeding, 

 of occasionally jerking the head and fore legs from side to side as if 

 annoyed by insects, although such was not the fact. Newman states 

 that when full-fed, the larva rests in a nearly straight position, is very 

 easily shaken off, generally falling on its back, when it immediately 

 turns over and begins to crawl, never feigning death nor rolling into a 

 ring. Harwood notes that the full-fed larva? generally hide themselves 

 very effectually during the heat of the day, and come out to feed in 

 the evening, when numbers may be found crawling and feeding, where 

 one might have searched in vain a few hours previously ; sometimes 

 they are to be found in the earlier part of the day, whilst the young 



