195 



or in the egg stage. According to Snellen and Barrett, 0. rooana is a 

 variety of 0. lacunana, SchifE. It is thus more or less clear that four 

 species of leaf-rollers attack strawberries. It is at least probable 

 that, whether as caterpillar or egg, the two species of Olethreutes pass 

 the winter above ground on the plants, and it would therefore appear 

 advisable to clean the beds thoroughly of all rubbish and dead leaves- 

 and also to remove all withered and damaged leaves from the plants. 

 In this way the majority of the eggs and larvae would be removed. 

 The case of the strawberry field which, though well cleaned, still 

 suffered somewhat, points to 0. schalleriana as the probable cause, 

 as these moths can find better shelter elsewhere than between the 

 strawberry plants, though still near to the beds, when they are driven 

 away by the removal of the rubbish. Some additional means of 

 destroying the insects being thus necessary, poisoning the leaves 

 with lead arsenate or Paris green suggested itself, but under the 

 conditions, it is very difficult to make the poison reach the larvae. 

 A stream sprayer was used which forcibly projected the solution in 

 drops of some size ; solutions of J per cent, lead arsenate and one-tentk 

 per cent. Paris green in lime-water were used on a badly infested 

 plot. It failed to penetrate the webs satisfactorily and a further 

 attempt made later was also unsuccessful. To be of any use, such 

 spraying must therefore be done earlier, before the webs are formed 

 or at least before they have any consistency. The time will depend 

 largely on the weather and on the district in question. The early 

 days of April appear to be the best time, so that the first food of the 

 caterpillars may be poisoned ; in any case before or about this date 

 the beds should be most carefully examined for any trace of attack 

 and action taken accordingly. The eggs are flat and oyster-shaped 

 and are generally laid in groups, being covered with a kind of varnish ; 

 the species of Olethreutes probably lay their eggs singly. 



RiTZEMA Bos (J.). Bene Belangrijke Vreterij van de Beuken-Borstel- 

 rups of den Roodstaart (Dasychira pudibunda, L.) in het Elspeter 

 Bosch. [Serious defoliation by the beech bark caterpillar or red 

 tail {Dasychira pudibxnda, L.) in the wood at Elspeet.] — Tijdschr. 

 Plantenziekten, Wageningen, xx, pt. 4, December 1914, pp. 115-140. 



In October 1914, about 125 acres of the beech woods at Elspeet 

 were completely defoliated by Dasychira, (Orgyia) pudihunda, L. 

 A few oaks scattered among the beeches were also practically stripped, 

 as was the undergrowth, which appears to have provided food for the 

 swarming caterpillars, M^hen the beech leaves had been consumed. 

 The buds were not greatly damaged, but a great quantity of one-year- 

 old twigs were found to be dead. The imago is on the wing at the end 

 of May and beginning of June and the eggs are laid on the trunks of 

 the beech in masses varying in number from 50 to 400, which have 

 a bluish-grey tint and are quite smooth and not covered with hairs, 

 as is the case in many allied species. 



A detailed account of the distribution of this pest is given, audit is 

 stated that the island of Riigen is notorious for its ravages. The 

 eggs are generally laid at from 6 to 10 feet up the trunks of the trees, 

 but when the invasion is very serious they will be found 12 to 18 

 feet above the ground. The caterpillars, which are described in 



