406 



The eggs, which are usually deposited in batches of twelve, may 

 be found on the upper surface of the leaves, the berries and their 

 pedicles, the stem, dry leaves or stones beneath the bushes, but the 

 favourite place is the under-surface of the leaves ; they are fixed at 

 the point of attachment and to each other by a gummy secretion. 

 Oviposition generally takes place at night, each female laying on 

 average 126 eggs, though the numbers vary greatly. The duration of 

 the egg-stage varies from 8 to 15 days, being shortest from. January 

 to April. 



The average duration of the first instar of eggs hatched in June, 

 July and August is from 14 to 15 days, and for those hatched from 

 December to January from 9 to 13 days. During this period the 

 insects seldom wander far from the egg-shells, but after the first 

 moult they become very active and feed voraciously. The average 

 duration of the second instar in July to September is from 32 to 67 and 

 in October to February from 13 to 20 days. The next two instars 

 have approximately the same duration, averaging about from 22 to 

 50 days for the earlier broods, the later ones being comparatively 

 shorter, whereas the 5th instar has an average duration of 22 to 32 

 days. After the 5th moult the insect acquires wings. 



There are about five species of Chalcids parasitic on^l. lineaticollis of 

 which two, though not yet identified, are here described and referred 

 to as " A " and " B." Experiments were made to determine the 

 length of life of these parasites, records of which are given in a table ; 

 that of " A " averages 6 days for males and 5 days for females, and of 

 " B " 3 days for males and 4 for females. These parasites also repro- 

 duce parthenogenetically, but in these cases all the offspring are males. 

 Under field conditions the numbers of females greatly exceeds that of 

 males so that parthenogenesis is comparatively rare. Both " A " 

 and " B " are foimd together in the field, but the proportion of one 

 to the other seems to depend on climatic conditions. Abundance of 

 the host-eggs and a high temperature seem to be more advantageous 

 to " A " than to " B," and further investigations are being made to 

 determine this point. There is every reason to believe that these . 

 parasites may prove a successful means of controlHng the insect as 

 the duration of their life-cycle is about \ that of their host. 



Owing to the affinity of this bug for sunshine, shade -trees may 

 prove of value as a means of control. The chief remedial measures 

 advocated are cultural methods, including immediate removal and 

 burning of all prunings and the stimulation of growth by manuring 

 and irrigation ; hand-picking is also recommended. Stomach poisons 

 have been tried, but without success, and experiments are now being 

 made to determine the efiiciency of contact-sprays. 



A comparison is drawn between some small differences in the 

 habits, etc., of this bug in British East Africa and Uganda. 



Washburn (F. L.). Some Useful Birds found in Minnesota: Their 

 Economic Relations to the Agriculturist. — Minnesota State Ento- 

 mologist, St. Paul, Minn., Circ. no. 43, 1st May 1917, 47 pp., 3 

 plates, 25 figs. [Received 26th July 1919.] 



This circular is a reprint of information that has already been 

 noticed [see this Review, Ser. A, iii, p. 161 and v, p. 465]. 



