INTRO D i XTION cxxi 



islands in consignments of sweet potatoes. The larvae is common not only in these, 

 but also in some of the wild Ipomoeas, especially /. pes-caprae. 



The 21 species oi Acalles are all endemic. They are difficult to collect and very 

 imperfectly known at present, and being often variable, with great sexual differences, 

 are still more difficult to separate specifically. Moreover examples in different condition 

 as to freshness have a very different appearance. Some of the species can, however, 

 be easily bred from dead wood, and until long series of many species are obtained in this 

 way their number will remain quite uncertain. With the exception of A. tuberculatus 

 found beneath small logs lying on the ground, all the species frequent standing trees. 

 They breed in dry dead branches, and are apparently absent from the wettest forests. 

 No parasites are at present known to attack this genus. The unique type of Chae- 

 7iosterniim has much the appearance of an abraded Acalles. Hyperomorpha sqiiaviosa 

 described (from a single specimen found near Honolulu) by Mr Blackburn, is probably 

 an introduction. I have felt some doubt whether this may not be Cryptorkynchus 

 batatas, an insect now common and attacking the sweet potato and other Ipomoeas, 

 and itself not a true Cryptorkynchus . Another recent introduction is the mango weevil 

 C. mangiferae, already after a few years' occupation, only too abundant on Oahu. 



Sphenophorus obscuriis is the well-known 'cane-borer' of the Hawaiian islands, a 

 most injurious species to sugar cane, but breeding also occasionally in bananas and 

 various palm trees. The Hawaiian and Tahitian form, introduced originally into 

 Maui from Tahiti, and later still reaching Fiji, is a different race from that found 

 in New Guinea and the Moluccas, the New Guinea form having also been imported 

 into Australia. The three species of Calandra are introduced, and include the common 

 rice-weevil, the tamarind weevil (C linearis var. striata) and a more remarkable species, 



C. remota. This latter is usually found in banana stems but also sometimes occurs in 

 those of coconut trees on the coast near Honolulu. 



The Cossoninae contain the most important and numerous genera and species 

 of Hawaiian weevils. The genera Deinocossonus, Nesotocus, Dysonima, Hetiramt)hus, 

 Oodemas and Anotheorus are endemic, while Orothreptes though not at present known 

 from elsewhere, will probably prove apodemic. There are 1 7 species of Drophthorus, 

 one of these D. distingiiendus being probably apodemic. The rest are true natives. 



D. distingucndiis is common in the town of Honolulu, often riddling boards, or wood that 

 is laid upon the ground in gardens. It is also very widely distributed throughout the 

 forests. Most of the species are polyphagous, their larvae attacking many kinds of dead 

 wood, either that of still standing trees, or of rotten logs lying upon the ground. Some 

 species, however, are more particular. D. oahuensis is usually found in the dead wood 

 of standing trees o{ Piptjcrns, and D.pnsillus inhabits decaying tree-ferns. D. viodestus 

 is also rarely found in the latter, as well as in many kinds of dead wood, hard or 

 decayed. The species are difficult to separate, and frequently colonies of several species 

 are found mixed. The remarkable little insect, for which I made the genus Thalattodora, 



F. H. I. q 



