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As regards the consequences of the outbreak of 1919 the author 

 beheved that many stands oi Pi iws sylveslris that seemed to have been 

 hopelessly defohated might recover. Where all appearances tend to 

 show that recovery is impossible, feUing should be quickly carried 

 out in the winter. A few trees that have kept some needles 

 should not be felled before the end of February or the beginning of 

 March, as they are needed as trap-trees for pine'beetles [Myeloj^hilus]. 

 These trap-trees must be removed about the end of May and the bark 

 must be burnt, as it contains the larvae and pupae of the beetles. 



It has been stated that an outbreak may last from 2 to 3 years. 

 As 1919 was the first year, in the case of many woods, it is likely 

 that infestation will be considerable in many places in 1920. Examin- 

 ation of the soil covering will show if pupae are present and if they 

 are parasitised or not. Wherever from 5 to 10 healthy pupae per 11 

 square feet are found it is advised that the soil covering be removed 

 and used as stable litter ; or if it is placed in heaps, the heat that is 

 generated will destroy the pupae. It is certain that in a locality 

 where infestation has occurred in the preceding year the number of 

 healthy pupae will be less than that of parasitised ones. In South 

 Germany the soil covering and moss is removed and piled up. After 

 being left thus during autumn and winter— during which period the 

 pupae are destroyed— the material is taken back to the wood and 

 again spread over the ground. A trial of this method was made in 

 one district in Holland in 1919, and it was noticed that many birds 

 cleared off the pupae on the uncovered ground. The driving of pigs 

 into woods should begin in July and the animals may remain there 

 until the frosts set in. The caterpillars and the moths may be jarred 

 from the trees by hitting the trunks with a club. Insecticides are of 

 practical value on a large scale. 



Much may be done to prevent outbreaks if a pine wood, when laid 

 out, is encircled by a girdle of deciduous trees and if the plantation is 

 of considerable extent it should be divided into sections by rows of 

 trees, which act as a barrier to the spread of infestation. Pines in 

 such mixed stands also sufter less from P. flammea, and mixed stands 

 have the further advantage of favouring insectivorous birds. 



La Plaga "Salivita" en la " Yerba Parana." [The Spittle-Insect, 

 Monecphora bicincta, Say, on Parana Grass {Panicum numi- 

 dia7ium).]~Cuba : Comision de Sanidad Vegetal, Havana, Circ. 4, 

 [n.d.] 31 pp., 8 plates. [Received 1st April 1920.] 



Parana grass {Panicum numidianum) forms the principal pasturage 

 in Cuba, and has lately been severely attacked by a Cercopid, Monec- 

 phora bicincta. This insect is of wide distribution in Cuba, where it 

 has beenknown since 1910, but its numbers are not very serious except 

 in unusually wet seasons. The life-cycle has not been worked out in 

 Cuba, but probably resembles that of Tomaspais saccharina {varia) 

 in Trinidad, where the eggs hatch in a mininmm of 12 days in wet 

 weather and during dry periods may remain unhatched for as long 

 as 4 months. The nymphal stage lasts from 32 to 40 days. In Cuba, 

 the maximum numbers occur in September, October and November. 

 The winged females oviposit on the ground near the pkuit or on the 

 plant itself, in moist places sheltered from the sun. The nymphs, 



