2ri8 Insect, Fungous and other Pests. .[July, 



of the leaf between the upper and lower epidermis, making 

 characteristic galleries. Once the maggot has got to work 

 inside the leaves it cannot be reached by any spray. The 

 infested leaves, therefore, should be pulled off and burned, or 

 the maggots may be destroyed by pinching the leaf between 

 finger and thumb. Various means have been tried in order 

 to keep away the adults and deter them from egg-laying. 

 Against a fly which attacks other plants in a similar way the 

 following spray is known to act as a deterrent : i oz. bitter aloes 

 and 2 oz. soft soap in i gallon of water. 



Holly-leaf Miner. — Other leaf-mining insects were forwarded 

 from Sunderland, these being the Holly-leaf Miner (Chroma- 

 tomyia ilicis) and the Marguerite Fly (Napomyia lateralis). 

 The former was destroying holly trees. The tiny black fly 

 lays its eggs in June on the mid-rib on the under surface of the 

 holly leaves, the maggot becoming full grown late in the next 

 spring or early summer. The fly issues from the pupa-case, 

 through a hole in the holly leaf, late in May or in June. During 

 the latter month, when egg-laying is in progress, the hollies 

 should be sprayed with paraffin emulsion or dusted with a 

 mixture of equal parts of soot and lime. Infested leaves should 

 be removed and burned. 



The Marguerite Fly (Napomyia lateralis) like the last named 

 insect, lays eggs from which come maggots that mine in the 

 leaf. To prevent the trouble spreading, infested leaves should 

 be removed and burned, or, in the case of a bad attack, the 

 whole plants should be destroyed. The female is deterred 

 from egg-laying if at an early stage the plants are sprayed with 

 paraffin emulsion. 



St. Mark's Fly. — A suspected case of Pear Midge from 

 Hadleigh, Suffolk, turned out to be a fly of the family Bibionidce, 

 for the most part of the species Bibio Marci, or St. Mark's Fly. 

 The flies of the genus Bibio appear as a rule early in the spring, 

 and as they often occur in large swarms, are supposed to be very 

 harmful, although in reality they are not so. The larvae of some 

 species are said to feed on the roots of grass, and the larvae of a 

 neighbouring genus, Dilophus, have been recorded as injurious 

 to the roots of hops. In general, however, eggs are laid in 

 decaying and decomposing matter, and the larvae are scavengers. 

 Notwithstanding the swarms which are seen about the blossoms 



