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appearance and have a superficial appearance of some crickets 

 rather than of more ordinary beetles. The species figured (Pla- 

 githmysus darzvUiianiis, Fig. 3) is one of those that attack the 

 "Mamani" on the Island of Hawaii. The larvae of these beetles 

 much resemble the borers previously mentioned, but are easily 

 distinguished by the absence of the small legs on the three seg- 

 ments of the body behind the head. Owing to the fact that num- 

 erous species attack the two common and important forest trees, 

 the Koa and Mamani. and that their work is so conspicuous on 

 the dead trees when the bark falls off. many complaints as to the 

 injury done by them to the forest have been received from va- 

 rious localities, but more especially from the upper forest country 

 of cattle ranches on Hawaii. 



The cricket-like beetles referred to in the previous paragraph 

 (fig. 3) which are so often reported from the forests as injur- 



FiG. 3 



ing the trees, are not only of interest from their peculiarities of 

 structure, but also from their habits. Nearly all the known species 

 described and undescribed (which at present exceed 50 in num- 

 ber) attack, each one, only one kind of forest tree. The excep- 

 tions to this rule are very rare. Some trees, like the Koa, Ma- 

 mani, Alani and Mamaki, have several or many species that feed 

 on them, but a good many native trees have never yet been found 

 subject to their attack. Other trees commonly affected by these 

 borers are the Ohia, Ohia-ha, Ahakea. Aiea, Xaeo, Heae, Akoko, 

 Koolea, Opuhe, and others more rarely. The stems of the Akala 

 are also bored by one species. There is no doubt that, injurious 

 as these borers appear to be, very few of them will attack trees 

 that are in a really healthy condition. As soon as a tree is in- 



