524 ALTERATION IN FLORA SINCE 



attacked by this larva, as are occasionally walnut (Juglans regia) and 

 a species of Eucalyptus. The larva of Melanchra (Mamestra) mutans, 

 Walk., frequently does very serious damage to the leaves of young 

 wheat, and considerable portions of the crops have been destroyed 

 at various times, particularly in the Canterbury district. M. composita, 

 Guen6e, known as the "grass-moth" or "grass-caterpillar," does 

 great damage and causes heavy losses to bush farmers especially. 

 Fortunately these animals are kept in check to a considerable extent 

 by certain ichneumons as Probolus sollicitorius, Fabr., Mesostenus 

 albopictus, Smith, as well as the introduced (?) Ryssa semipunctata. 



Liothula {(Eceticus) omnivora, Fereday, has occasionally done much 

 damage among raspberry plantations. 



The caterpillar of Ctenopseustes ohliquana, Walk., which usually 

 feeds on manuka and other native shrubs, has developed a fondness 

 for the ripe fruit of plums and apricots. 



The larvae of Caccecia excessana, Walk., attacks the outsides of 

 apples, and these have frequently been sent in to the Agricultural 

 Department under the impression that they were attacked by the 

 larvas of the introduced codlin moth {Carpocapsa pomonella). The 

 latter, however, attacks the core of the fruit, while that of Caccecia 

 only attacks the outside. This insect also attacks and disfigures the 

 cherry-laurel {Prunus lauro-cerasus). 



Two native species belonging to the Caradrinidas may be men- 

 tioned in this connection. Agrotis ypsilon, Bott., is known in New 

 Zealand as the tussock moth, the larvse doing considerable damage 

 in tussock country; it is also a very common pest in vegetable 

 gardens. In Hawaii, where it is known as the greasy cutworm, it is 

 very prevalent, and attacks cotton and tobacco. 



Cyrpkus unipunctatus, Hawthorne, which is very abundant in the 

 North Island, occasionally attacks grain crops, but is apparently kept 

 in check to a considerable extent by birds. In North America it is 

 one of the most serious of the cereal crop pests. 



Among Coleoptera only a few instances are recorded. 



(Emona humilis, Newman, attacks lemon trees in the northern 

 orchards, and eats into the wood. 



Xyhteles griseus, Westwood, has been reported several times as 

 attacking fig trees, while X./tefiw, White, sometimes called the " apple- 

 borer," occasionally destroys the apples on the trees. 



All three species of beetles belong to the Cerambycidse, one of 

 the few families reported to contain destructive pests, but none of 

 them have become serious. 



The larva of Odontria striata, White, commonly known as the 

 "grass-grub," is a very destructive insect, especially in pastures and 



