833 



sonnnvhat loiigcr pliniies, r. (/<)r.s(t/is bccoincs siimllci'. The pro- 

 thoracic shiold has disappeared. 



Instar IIL Duration 8 days. Loii<>tli 15 luin. As instar //. 



Tiistar IV. Duration 6 days. Ijciigth 24 mm. As instar //, tlio 

 sidos of tln^ head beoomo grey. 



Instar 1^ Duration 11 days. Ijength 35 mm. As instar If 

 but somt' soeundary setao appear on the body and the v. mfra- 

 stigDiales are sometimes divided into many pieces, on the thora- 

 cic segments the v. pedales are wanting. 

 Piqja. 



On the abdomen of the pupa the verrucae are arranged in a 

 distinct way according to type Ih. The furrow between v. t^Npra- 

 stif/inalis and v. poatstujniaUs has grown larger. 



The setae on the pupa too are plumed. Distinct are : v. (/orsa/is 

 even larger than on the caterpillars, v. subdorsalis^ i\ sitpncsfü/- 

 nialis + V. jwststigmalis, v. mfrastigmalis^ v. basalis and a far 

 projecting i\ 2'^^dalis. 



Euproctis (Porthesia) rJiri/sorhoea Linn., Plate XI, fig. 12 — 15. 



Material in alcohol, from Groningen (spring 1915) and living 

 material from the Hague (autumn 1914). 



I have not been able to obtain the newly hatched caterpillars 

 of this species. The youngest are of December 19th 1914. They 

 were found in a nest on Hippophaes rhamnoides Linn. and as 

 in the course of their development they cast the skin four times, 

 and were only 4 a 5 mm. long, I have described them as 

 instar I. 



Instar /. Duration at least 130 days, they hibernate. The first 

 monlting took place on April 27th. Length 4 mm. Tubercula 

 formed like warts. 



The setae are not plumed, + 1 mm. long. 



The colour pattern is very intricate, there is a distinct median 

 dorsal line. 



Prothorax. Both the r. dorsales from the left to the right are 

 connected by a distinct prothoracic shield. The v. subdorsales are 



