372 Insect Pests. 



appear to enter at any wound, and thus it would be well to clean all 

 wounds and fill in with wax or Stockholm tar. 



A full account of this insect will be found in Hubbard's report (2 ). 



Eeferences. 



(1) Onnerod, E. A.. ' Handbook of Insects Injurious to Orchard and Bush 



Fruits,' p. 192 (1898). 



(2) Huhhard, H. J. The Ambrosia Beetles of the United States. Some 



Miscellaneous Results of Work of the Division of Entomology. U.S. Dept. 

 Agriculture, Washington, p. 24 (1897). 



(3) HopTxins, A. D. " The Wood Engraver " Ambrosia Beetle. Canadian 



Entomologist, No. 2 (1898). 



THE PLUM LEAF SAWFLY. 



( Cladius padi Linna'us.) 



There exist two species of sawflies which attack the plum in this 

 country. One may frequently be seen, namely, the Plum Leaf 

 Sawfiy, the Tenthredo ]}adi of Linnaius, now known as Cladius padi. 

 The second is the Hoplocampa fidvir.ornis, King, which in the larval 

 stage feeds inside the young plums and speedily causes them to fall 

 (vide p. 376). The leaf-eating species does considerable damage 

 when very abundant, but, fortunately, although widely distributed 

 over the British Islands (1), it does not often occur in sufficient 

 numbers to do any appreciable amount of harm. During 1906 two 

 attacks were reported where the plum trees had every leaf 

 spoiled by the larva?. It occurs even at considerable elevations, 

 Cameron (1) having taken it at 2,300 feet in the Scotch mountains. 

 It is found over most of Europe, where it is now and again recorded 

 as being of an injurious nature. 



There do not seem to be any published records of its causing 

 damage in Britain except the record in the S. E. College Journal (2). 



The food plants, besides plum, are pear, rose, hawthorn, bramble, 

 mountain ash and birch. It occurs on both wild and cultivated 

 roses, and I have found it on wild prunes, such as bullace and sloe. 

 Mr. C. 0. Waterhouse has bred it from cherry at Acton, where he 

 noticed it doing much damage. 



The damage is done entirely by the larva? eating the leaves. 

 In the early stages of the attack the leaves resemble those infested 

 with the Slugworm (UriocamjM limacina), but the upper, not under 

 epidermis, remains intact ; the young larvee eat the lower epidermis 

 and soft mesophyll tissues and leave the upper epidermis. It differs 



