cosmotriche potatoria. 173 



larval hairs are very numerous, lightly attached to the surface, the 

 very fine ones especially thick at the ends and along the groove 

 that runs parallel and near to the line of attachment to the grass 

 culm or other object on which the cocoon is spun, this groove 

 being, in some cocoons, very sharply and clearly marked. The 

 interior of the cocoon is paler than the exterior, and is also less papery 

 in texture, there being a thin internal coating of fine shiny silk 

 (Bacot). The emerging imago stains the exit with a thick brownish 

 fluid, but the great mass of this material is discharged into the 

 pupa-case. Dalglish notes : " Cocoon sott, closely woven, similar to 

 a piece of thin tough parchment, greenish-white in nature when 

 fresh, very thin at bottom." 



Pupa. — The pupa is of a black-brown colour, the segmental 

 incisions between 4-5, 5-6, 6-7 abdominal segments, the legs, 

 antennae, and mouthparts being of a bright red-brown. Dorsally : 

 prothorax black, large ; prothoracic spiracle deeply set in the 

 incision between the prothorax and mesothorax and almost in 

 contact with the antennae, and having a raised black rim ; the meso- 

 thorax, black, large, and swollen dorsally ; the metathorax small, 

 much reduced medially, broader at the sides where it gives oft 

 hindwings ; the first abdominal segment narrow with a median 

 depression; the second, third and fourth gradually increasing in 

 size, fixed, although the intersegmental membranes are recognisable ; 

 movable incisions exist between 4-5, 5-6, 6-7 ; the skin of the 

 segments is black and finely pitted, that of the intersegmental mem- 

 branes reddish-brown and with the appearance of silk ; the 8th and 

 9th abdominal segments with fine, black, bristly points, the cremastral 

 area covered with fine short golden-brown bristles ; the cremaster 

 rounded. Laterally : the pupa is swollen at the metathorax and 

 on the wings in the neighbourhood of the 3rd and 4th abdominals; 

 the wings black with raised nervures ; spiracles on the 2nd — 8th 

 abdominals, each consisting of an elliptical opening with a raised 

 black rim, situated in a shallow depression. Ventrally : Mouth-parts 

 situated ventrally, black ; lunular glazed-eye red-brown, extending 

 from near the base of antenna to the first pair of legs ; the labial 

 palpi and maxillae placed between the first pair of legs ; the 

 second pair of legs ending between the tips of antennae ; the 

 antennae (<?) distinctly segmented but without showing the distinct 

 pectinations of the imago ; the claws of the third pair of legs 

 extend just below the apices of the wings ; the anal area rounded ; 

 the sexual organs set very far back on the 9th abdominal segment 

 (Tutt. July 19th, 1896). $ pupa '875m. in length, -3m. in 

 diameter; ? pupa iin. in length, '375m. in diameter*. Pupa- 

 skin thin and delicate, very dark brown in colour, almost black 

 on thorax, paler on the venter of abdominal segments ; the anus 

 is very blunt and evenly rounded off; the $ pupae are more obese, 

 and taper less towards the ends than do the $ pupae ; surface 

 smooth, shiny in places ; the only hairs to be detected are very 

 minute, bright brown in colour, situated on the anal segment or 



* These measurements are made from empty pupa-cases ; a pupa, in which 

 an unemerged s had died, measures, at full stretch, nin. in length, -3m. in diameter 

 (Bacot), 



