NOTES ON CJORTYNA OCHRACEA (fLAVA<;o). 15 



pink; discal dot. and dots representing elbowed line, very small and indistinct, 

 hindwings whitish-grey with nervnres slightly darker = ab. ptillitla, n. ab. 



4. Forewings rosy-butf ; discal dot, and row of dots representing elbowed line, 

 small, but distinct; hindwings pale rosy, with nervures conspicuously shaded with 

 dark brown = ab. fiisco-roscd, n. ab. This is a delicate and beautiful aberration. 



Notes on Gortyna ochracea (flavago). 



By J. W. H. HAIUUSON, li.Sc. 

 I have been attracted to this species by the fact that there is sonie- 

 thing curious about it. It is generally assumed that it passes 

 some five months in the larval condition. I am inclined to think that, 

 here at least, it often passes at least seventeen months in that state. 

 For some years, I have always been surprised to note that, when splitting 

 the stems of the foodplant for pupse, especially when the food was 

 Canlniis /lalKstris or Artcntisia ridf/ari.s, small larvie of (r. oc/iracea, 

 about 12ium. long, were present. I had generally concluded that these 

 never reached maturity, being killed by the frosts of the winter. In the 

 last week in March this year (1901), however, I was looking for larv:B of 

 Xi/lDphasio nirca, which delight to hide in thistle-stems during the day, 

 when I came across a larva of G. ochracea inside a dead stem, and this larva, 

 to judge by the frass, was feeding freely. I then searched further and 

 found other larvfB in different stems. These larvfe all averaged about 

 l-5cm. long. Thus it would seem that the larvte feed throughout 

 the winter inside dead thistle-stems. There was no chance that 

 these were cases of the early hatching of ova, followed by rapid feed- 

 ing up, as this season was very backward here. The ova, when kept 

 indoors even, do not hatch until March and April. Here the pupte are to 

 be got freely during the first and second weeks in September, inside the 

 stems of the foodplant. Upon the coasts of Durham and Northumber- 

 land, the foodplants are Cardidis arrensis and Smeciti jacnhaea. Inland, 

 the foodplants are the common-thistle, the marsh-thistle, and mug- 

 wort, but especially the last. The pupa; are found head uppeniiost in 

 a cell, consisting of the hollow stem with a pad of frass and silk at 

 the bottom. Just above the head is a large round hole, perforated by 

 the larva, to allow of the easy exit of the imago. At intervals up the 

 stem are holes, out of which the larva, as it proceeds down, ejects its 

 frass. The pupjc are largely preyed upon by earwigs, even when 

 healthy, but still more destructive is a large species of ichneumon, 

 which passes the winter as a fullgrown larva inside the pupa, for 

 I found several on Christmas Day, 1902. The female pupa is easily 

 recognised from its size, being much elongated, whereas the male is 

 little more than half the size. Generally speaking, more female pupa- 

 are obtained than male, probably owing to the fact that the fenuile 

 larvse, eating more food than the male, weaken the stem to such an 

 extent that it bends over in nearly all cases, thus betraying the exist- 

 ence of a pupa inside. Usually one pupa is found inside, but, in rare 

 cases, two are sometimes obtained. Once I was fortunate enough to get 

 three pupsc from one mugwort stem. The insect enaerges in the third 

 week in September. If one examines the stems between 8 a.m. and 

 10.80 a.m., the iraagmes are to be found expanding their wings 

 and are by no means easy to see, as I have often, while grasping a 

 stem, taken hold of an insect without seeing it. Tlie female generally 

 lives about 25 days — at least I have found this to bo the case in 



