72 



think that there they serve for the dispersion of the larvae by 

 the wind. In that case, however, they should have been much 

 longer, for these small vesicles with a radius of ± 10 /!/., cannot 

 excercise any influence on the specific weight. Moreover, the long 

 setae are more suitable for this purpose. It is certainly remark- 

 able that these setae only occur . in the first instar both on 

 Lijmantria dispar and on Lymantria monacha. Their function is a 

 riddle to me; for the time being, I identify these setae with the 

 glandular hairs which often occur in a first instar. Directly after 

 hatching, the head is coloured black, the tubercula become 

 coloured later on. 



The following tubercula are visible: 



Prothorax. Small v. dorsalis with short setae, rather large v. 

 xKbdorsalix on which the setae mentioned sub. 2 are present 

 (this verruca is connected with the preceding one by an indistinct 

 prothoracic shield); a far projecting v. suprastigmalis with which 

 V. prostigmalis is connected, v. infrastigmalis, v. basalis and one 

 V. ventralis. 



Mesothorax and metathorax. Very large v. dorsalis^ small v. 

 dorsolateralis, large v. suprastigmalis, a long drawn v. infrastig- 

 malis, V. propedalis, v. basalis, v. ventralis. 



Abilomen 1. Very small v. dorsalis and an extraordinarily large 

 V. subdorsalis. The verruca over the stigma is divided into two 

 parts by a furrow. The front part is v. suprastigmalis, the back 

 part V. poststigmalis ', v. infrastigmalis is elongated, v. basalis 

 small, no v. pedalis. 



This pattern I have called type lb. 

 Segm. 2=1, but v. infrastigmalis consists of two parts, one be- 

 hind the other. 



„ 3, 4, 5, 6 = 2, but V. basalis is absent. 



„ 7, 8, 9 = 2, but on 9 the verrucae are much higher than 



on the other segments. 

 „ 10 is strongly reduced, the verrucae are not distinct. 



Instar //. Duration 12 days. Length 8 mm. The same as 

 instar /, but the peculiar setae have disappeared. The setae bear 



