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for seed or for food. The eggs are laid anywhere on a potato, but never 

 on the sprouts or directly on an eye bud. As the female shuns light 

 the eggs are always laid on that side of the tuber which is furthest 

 from it. The egg-laying capacity is probably enormous, as the adults 

 live seven or eight months. The various stages are described. As the 

 insect is long-hved and oviposits many times during its Hfe it is hardly 

 possible to speak of distinct broods, but in the laboratory the cycle 

 from egg to adult was found to be about four weeks and the possibiUty 

 of at least seven distinct broods in a year was demonstrated. The first 

 insects appear in the godow'ns soon after storing, but the then 

 prevailing dry conditions prevent rapid multiphcation. The method 

 of storage prevents proper observation, as the potatoes are put into 

 baskets and stored on staging in the godown and are never touched or 

 disturbed during the whole storing season, so that the cultivator does 

 not see the pests till they have multiplied to such an extent as to be 

 obliged to come to the surface to find food, and it is probable that 

 at least one if not two broods occur before the break of the monsoon 

 in June. Hibernation in the egg stage is very improbable, considering the 

 conditions required, and as neither maturing nor oviposition occurred 

 in the laboratory from the end of December to the beginning of March, 

 it is almost certain that hibernation takes place in the adult stage. 

 Both as nymph and adult, the insect sucks the sap from the cortical 

 cells under the skin of the potato and the work begins immediately 

 after hatching. The excreta stain the potato skin yellow, and when 

 the colony is numerous late in the season, the entire tubers become 

 moist, as if dipped in water ; this excretion in a few weeks turns a 

 sooty black. Though the pest only operates over a hmited area at 

 present and will probably only spread slowly by natural means, the 

 loss to the cultivators is very serious. There is also danger of its 

 mechanical spread, as Bettiah is a very important centre for the export 

 of seed potatoes in the Tirhut Division. The annual crop has risen 

 from 600 tons in 1908 to over 1,500 tons at the present time. This 

 export goes on all the year except December and January, and the 

 traffic during the latter part of the storing season can only be regarded 

 as risliy in the extreme, although it is obviously useless to attempt to 

 sell badly infested tubers. No parasites of any kind have been found, 

 but the common red ant, Monomorium indicum, Forel, attacks the pest 

 freely. The preventive measures suggested are control of the potato 

 traffic in places where the pest is prevalent and destruction of infested 

 material. The method of storing is largely to blame for the increase 

 of the pest and four tests were made with a view to improving this. 

 Four equal quantities of potatoes were stored, each in eight baskets 

 as follows : — (1) In baskets without mud or sand covering (local 

 method), (2) in baskets plastered with mud and covered on the top 

 with dry sand, (3) as (2) but with naphthalene balls, not sand, (4) in 

 baskets plastered with mud, and covered with sand and with napthalene 

 balls. All affected and rotten tubers were picked out and rejected once 

 a month. The plastered and sanded baskets were practically free, 

 whilst the check baskets were seriously infested. Unfortunately the 

 method induces rotting under the moist conditions of the locality, but 

 worked well in the drier chmate of Patna. Further experiments on 

 fumigation, other methods of storage and improved ventilation are 

 in progress and will be reported on. 



