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~ The Coccinellids, Exochonms quadripustulntus, L., and Hyperaspis 

 campestris, Hbst., are both active enemies of. aS. prunastri. The former 

 oviposits in spring in the bodies of female scales of the previous year 

 that have been killed by parasites and the resulting larvae attack 

 the young scales. H. campestris occurs throughout Europe, but is 

 not common. Its larva infests S. pmnastn m the same way that 

 H. binotata, Say, in North America attacks Eidecanium fiigrqfasciatum, 

 Perg., Pulvirmria vitis, L., and other scales. In Italy the adult 

 Coccinellid occurs in June and July and oviposition begins in the 

 second half of June. In the first three larval stages moulting takes 

 place beneath the host-scale. Pupation occurs on the twigs from 

 mid- August onwards, and the resulting adults hibernate. Some of the 

 larvae of H. campestris are parasitised by a Chalcidid, Homalotylus 

 flaminius, Dalm. 



An Acarid, Pediculoid.es ventricosns, Newp., is occasionally observed 

 in dead female scales containing hibernating larvae of Phaenodiscus 

 (leneus, on which it feeds, especially from September to May. 



A Chalcid, Coccophagus scutellaris, Dalm., infests from 1 to 5 per 

 cent, of the scales. It is found throughout Europe and probably 

 has been introduced into America. It is also known as a parasite of 

 Eidecanium coryli, E. persicae, FUippia {Philippia) oleae, Saissetia 

 oleae, Ceroplastes rusci, and Pulvinaria mesembryanthemi and probably 

 infests all other European Lecaniines. Coccophagus howardi, Masi, 

 which possibly occurs throughout Europe and is known to parasitise 

 Filippia oleae and Ceroplastes rusci, has similar habits and probably 

 infests other scales. 



Phaenodiscus aeneus, Dalm., which is fully described here, has 

 been hitherto recorded from Sweden, Germany and Austria. Jn 

 Italy cases were observed where nearly 100 per cent, of the females of 

 S. prunastri were parasitised by it, though many of their progeny 

 escape owing to death being delayed until the eggs are laid. This 

 Chtilcid is furthermore itself hyperparasitised by others such as 

 Cerapterocerus mirabilis, Pachyneuron coccorum and Perissopterus 

 zebra. The first adults of this Chalcid emerge in April from dead 

 females of S. prunastri and the eggs of the first generation are laid 

 in 4th stage females of this scale. Adults appear in about one month 

 and they oviposit in female scales that have either not begun or not 

 finished ovipositing. The resulting larvae remain in the host until 

 the following April. Phaenodiscus aeneus has therefore two genera- 

 tions a year. It must be considered a special parasite of S. prunastri ; 

 the author doubts whether his previous record from Eulecaniwn 

 (Lecanium) persicae is correct, while that from Diaspis rosae is certainly 

 incorrect. 



Cerapterocerus mirabilis, Westw., which is described, has been 

 recorded from England, Germany and Austria. In Italy it occurs 

 in the same localities as Phaenodiscus aeneus. The female is apparently 

 unable to detect whether the female scales of S. prunastri actually 

 harbour Phaenodiscus or not, for oviposition has- been observed in 

 non-parasitised scales. It hibernates in the larva of Phaenodiscus 

 and the adult appears in May. It is an important hyperparasite, 

 for from 30 to 50 per cent, (sometimes even 70 per cent.) of the larvae 

 of Phaenodiscus may be attacked. 



