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elongated fragments ; while P. vcimtor also uses roundish frag- 

 ments, but the cocoon is more carinated. 



The cocoon of Chlorodryinus is long, narrow and cylindrical 

 and no fragments of leaf substance are woven into the surface. 

 That of Ncodryiiiiis is ovate and the upper and lower walls of 

 the marginal part are strengthened with great numbers of verti- 

 cal pillars. In addition as above mentioned, the larger part of 

 tlie ruptured larval sac is removed from the hopper and attached 

 as a roof over the cocoon. This sac being of the usual circular 

 form, when ruptured by the escaping larva, gapes open like a 

 bivalve shell, as do those of all other Dryinidae known to us. 

 These two valves are stretched wide open over its cocoon by the 

 mature Neodryinus larva, and so fastened, the whole forming 

 a subovate or subreniform roof over just so much of the whole 

 cocoon as covers the insect within. Of what use to the genus 

 this extra shelter may be, we cannot conjecture. It certainly 

 does not make the cocoon less conspicuous, as do the fragments 

 from the surface on which it pupates that of Paradryimis, 

 nor yet does it keep out the spores of fungi to which both genera 

 and some others are very liable. All the known hyperparasites 

 attack the larva before the cocoon is made and not afterwards, 

 so they do not enter into the question. 



The cocoons of the short-legged genera, with large ovate 

 stigma to the front wings are almost certainly under natural 

 conditions subterranean. They are of shorter, wider form than 

 those of the more highly evoluted group of genera; in fact, often 

 nearly round, and are covered with particles of the soil or debris 

 amongst which they are formed, so as to be most difficult to 

 detect by sight. 



LARVAL SAC OF DRYINIDAE. 



The larval sac of the Dryinidae is of circular form, the sides 

 being more or less compressed according to the species. The 

 colour is frequently uniform, but in some species it is more or 

 less, or even conspicuously, variegated. Towards the point of 

 attachment the surface is often nearly smooth and sometimes 

 shining, but externally more or less rugulosely sculptured. This 

 sculpture is sometimes so well-marked and the pattern so regu- 

 lar, that under a strong lens the surface of the sac presents a 

 really beautiful appearance. In some species the external rugu- 

 lose portion bears short, stiff, erect, bristles. The larval sac is 

 formed of the skin of the curled up larva together with one or 



