10 



The larval stage occupies about 26 days. Before pupating the 

 worm usually leaves its mine or tunnel and rinding a hidden or 

 obscure corner builds a cocoon of silk and grass or grains of soil 

 within which it pupates. 



The pupa: The pupa, removed from its case, is brown, about 6 

 mm. long, and rather slender. The wing cases distally are free from 

 the abdomen; the leg and antennal cases are scarcely longer than 

 these, and reach the apex of the sixth segment. The cremaster is 

 lobed, and between the lobes dorsally is a short, stout spine surrounded 

 by numerous hairs with recurved tips. The pupal stage covers 11 

 days. 



The moth: The moth is described by Walsingham 1 as follows: 



Antennae brownish cinereous. Palpi cinereous, with two umber-brown patches 

 on the median joint externally, a spot of the same on the base of the terminal joint 

 and a broad band before its apex. Head brownish cinereous; face pale cinereous. 

 Thorax brownish cinereous, with three smoky brown longitudinal lines above. 

 Fore wings dull buff -brown, shaded and spotted with dark smoky brown; this forms 

 a dorsal shade below the fold, a terminal shade reverting around the apex, and a spot 

 at the end of the cell from which narrow lines radiate outward along the veins; there 

 are also two spots near the base of the costa, the first succeeded by another below and 

 beyond it, the second followed by one on the cell and one on the fold in an oblique 

 line, a pair of smaller spots lying beyond thi3 line on the cell, also in oblique succes- 

 sion; cilia pale buff -brownish, sprinkled along their base with smoky brown. Exp. 

 al. 15-16 mm. Hind wings pale gray; cilia pale brownish ochreous. Abdomen and 

 legs brownish cinereous. 



Remedies. — As the insect in its injurious stage is generally protected 

 in its tunnel, poisons are of little use in attempting to control it 

 artificially. It is well known, however, that the worm often deserts 

 an old mine to form a new one and the hatching caterpillars must in 

 the first place eat through the epidermis; to this extent, therefore, 

 they are vulnerable to lead arsenate dusted or sprayed on the plants, 

 and this measure is recommended for the control of the worm in seed 

 beds. If the arsenic is applied as a spray it can be combined with 

 the Bordeaux mixture used in case of fungus troubles. Under field 

 conditions, however, the little good accomplished and the great 

 expense involved make it scarcely worth while. As already men- 

 tioned, the beds can be protected by screening. As a precaution 

 against a general infestation, no solanaceous plants should be grown 

 near the tobacco fields and all solanaceous weeds in the immediate 

 vicinity should be periodically destroyed. 



Natural enemies. — The caterpillars of the splitworm are very much 

 parasitized by a small black and white braconid, CJielonus blaclibumi, 

 which likewise attacks a number of other small leaf-rolling cater- 

 pillars. The parasitized caterpillars spin their cocoons when about 

 half grown without pupating. Shortly afterwards the larva of the 



I I^auna Ilawaiiensis, vol. 1, pt. 5, p. 484, 1907. 



