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eggs have been counted beneath one female. The young larvae 

 migrate from the twigs to the leaves, to theunder-surface of which they 

 attach themselves near a vein ; if the leaves are little exposed to light, 

 attachment may take place on the upper surface. Moulting occurs 

 in September and the second-stage female larva attaches itself to 

 the twigs. It moults at the end of February or early in March. The 

 second-.->tage male larva also appears in September and moulting 

 also takes place about the end of February. The first adult males 

 were observed on 22nd March. The injury done by E. coryli is due 

 to the scales sucking the pi ant- juices, chiefly at the end of winter 

 and early in spring. It is rarely serious, because infestation is slight. 

 Weather conditions exercise no great direct influence on the scale. 

 Natural enemies include some undetermined fungi and the following 

 insects : — 



Ooleoptera. The Coccinellids, Chilocorus hifusUdatus, L., and 

 Exochomus qriadripuslulalus, L., do not greatly reduce the numbers 

 of E. coryli, because other scales provide abundant prey. Anthribus 

 fascialus, Forst., is known throughout Europe and its distribution 

 should coincide with that of E. coryli, but at Portici it was not found 

 during three years, although the scale was present. In the Province 

 of Caserta the adults appear in June and in the following April they 

 prey on E. coryli. It was not possible to ascertain what their food 

 was during the intervening months. The eggs are laid beneath 

 the scale, where the larvae feed on the eggs of the latter and pupate. 

 The adult Anthribids pierce the back of the scale and emerge. The 

 life-cycle requires a Uttle under two months. About 50 per cent, 

 of the scales are attacked. In 1915 Munemoto Yano recorded 

 Anthribus niveovariegatus as destroying the eggs of another Coccid, 

 Ericerus pela, Chav., in the Far East. 



All the Hymenopterous insects mentioned are Chalcids. Encyrtus 

 infidus, Rossi, probably occurs wherever E. coryli is found in Europe, 

 but Imms, who recently worked on the parasites of this scale [R.A.E., 

 A, vii, 194], does not record it in England. At Portici the first adults 

 emerge from E. coryli towards the end of March. At the end of 

 Marcii or early in April the female lays a number of eggs (frequentlv 

 from 4 to 15) in a female scale. From eggs laid on 29th March the 

 first larva appeared on 4th April. After four moults pupation takes 

 place. Larvae hatched on 4th April yielded prepupae on the 18th, 

 pupae on the 20th and adults on the 28th. In several hundred larvae 

 of E. coryli examined from July to November no eggs or larvae of 

 Encyrtus wfidus were found, though many were parasitised by Apkycus. 

 It therefore seems that the first generation of E. infidus (developed 

 in E. coryli) either has an intermediate host or waits in the adult 

 stage until autumn in order to oviposit. The fir^it generation larvae 

 of E. wfidus often fail to kill the scale before it has finished ovipositing ; 

 those of the second succeed in killing it while yet immature. In 

 observed cases the percentage of parasitism was from 20 to 50 per 

 cent. 



Blasfofhrix sericea, Dalm., has been recorded from Sweden, England, 

 Germany and Austria, and must occur in other parts of Europe. 

 At Portici the first adults appear early in April and about two days 

 later from 1 to 12 or more eggs are deposited in the last-stage females 

 of E. coryli. It is probable that the larvae have 5 stages, though 



