1. From the study of the historical records of European invasions by Locusta from the 14th century to the present day, it is concluded that the subspecies concerned was L. m. migratoria originating in the West Pontian outbreak area. This area formerly comprised the lower courses of rivers draining into the Black Sea from the Danube to the Dniepr inclusive, and is now confined to the delta of the Danube. From here swarms migrated into central Europe and the eastern part of the north European plain. The northern part of the plain, the British Isles and Fenno-Scandia, lie on the outskirts of the invasion area, and as a rule were only reached by small detachments from swarms. The decline of the West Pontian outbreak centres was accompanied by the gradual decline of the area subject to invasions by large swarms, but during outbreaks small groups and separate individuals of ph. gregaria continue to reach the further limits of the invasion area.

2. The distances covered within a single generation by swarms of L. m. migratoria in temperate Europe (up to 1,600 miles) were comparable in extent to those traversed by L. m. migratorioides in tropical Africa.

3. Long-range migrations to the extreme limits of the invasion area are not confined to L. m. migratoria ph. gregaria but occur also in ph. solitaria. This is shown by the arrival of individuals of this phase in the British Isles during theperiod when the West Pontian outbreak areas are in a quiescent state. From this and from literature data on other locust species it is concluded that long-range migration is a regular seasonal phenomenon in swarming acrididae, independent of the presence of large numbers or the phase.

4. The late summer immigration of L. m. migratoria into the British Isles may be a part of a more general east to west movement of flying insects which may occur in Europe at that season.

5. It is probable that L. m. migratoria sometimes oviposit in the British Isles, for they may arrive in a mature state, or during exceptionally hot summers in southeastern England they may reach sexual maturity after arrival. The eggs, however, are apparently unable to survive winter conditions.

During the last twenty years, the Forestry Commission, several local authorities, and a large number of private woodland owners, have expended a total of several million pounds in an endeavour to replace the stocks of growing timber which were so heavily depleted during the last war. Several hundred thousand acres have been planted and a large proportion of these areas have been stocked with coniferous species.

1. The investigation which forms the subject of this paper was commenced in 1936 and closed in 1939. Owing to the low returns from an acre of coconut land it was imperative that control measures should be cheap. Biological methods were therefore employed.

2. The soils on which coconuts are planted in Seychelles fall into three main types: (a) beds of coral sand, (b) various types of transported soils, (c) sedentary soils.

3. The robustness of the trees was found to be in direct proportion to the quality of the soil. The best trees are located on the deeper alluviums. The limiting factor on the coral sands is often drainage. On the hill-sides the trees deteriorate in proportion to the soil impoverishment and erosion.

4. A complex of scale species attack coconuts in Seychelles. None of these presents major problems in other countries, and the better known scales which are pests on this crop in other countries are not found in Seychelles. Four major species are mentioned, two of which are recent introductions to the islands. The life-history and particular requirements of each species are given and their incidence on coconut and their interspecific relationships are discussed.

5. In order to combat these scales four species of Coccinellidae were introduced from East Africa, two of which were predators on Diaspid and two on Lecaniid scales. The life-history, breeding technique and establishment of each is described.

In Vol. 29 (March, 1938) of this journal a short summary was given of the results achieved during an investigation of the wood-destroying insects in public buildings in the southern part of Sweden, Götaland. This survey has since that time been continued in Svealand, the middle part of Sweden, and in the following a short summary of the results will be given.

The research work involved in this paper was financed by Messrs. Levers Pacific Plantations Pty., Ltd., of Sydney, and I wish to acknowledge the help and courtesy extended to me by so many members of their staff.