INTRODUCTION IxxxHi 



XvLOCOPiDAE. — Xylocopa brasi/ianoruni (or aeneipeimis) is an abundant and even 

 injurious species, since it does considerable damage by riddling fence-posts, telephone 

 poles and other wood with its borings. It also burrows in living trees, but I think only 

 in the dead parts or such as are nearly dead, choosing generally the softest kinds of 

 wood. I think there is no doubt that it was imported by man in lumber. It was 

 unknown until after the islands were settled by foreigners. It is interesting to note that 

 its habits are such, as might have enabled it to reach the islands by natural immigration, 

 for it is particularly fond of breeding in dead logs on the sea-beaches, especially in the 

 very light, dry logs of the ' wiliwili ' [Eryihrina). It is also very partial to the dead 

 branches of this tree, when still growing. This Xylocopa chiefly inhabits the littoral or 

 low mountain regions. It visits many kinds of flowers, especially papilionaceous ones. 

 The larvae and pupae are often destroyed wholesale by the foreign ant Plieidolc mega- 

 cephala, which enters the burrows in swarms, and we have seen a whole colony of the 

 bee eliminated by this minute enemy. 



Megachilidae. — ^The three Megachile are probably all introduced, two indeed 

 are of recent importation and have increased their range and numbers enormously in 

 the last 1 6 years. M. diligens is widely distributed over the islands, but shows no 

 local variation. It was found by Mr Blackburn in Honolulu more than 30 years 

 ago, but we have no record of its distribution at that time. It still is found in the 

 gardens in Honolulu. In the country it is generally found along the coasts or lowlands. 

 Its nests are formed of leaves of various imported Acacias. On sandy coasts we have 

 observed the bees very plentifully in the flowers of Iponioea pes-caprae, but it visits 

 those of other naturally immigrant or native plants, and in gardens in Honolulu has 

 been taken on Cosuios, Plumbago and various introduced flowering shrubs. 



M. schauinslandi is, I have little doubt, an Asiatic importation. It is not a leaf- 

 cutter like its two congeners, but seals up keyholes and cavities, in which it breeds, with 

 masses of resinous matter. It is extremely abundant in gardens in Honolulu, visiting 

 many kinds of flowers of cultivated plants as well as weeds. 



M. palmai'iini was probably introduced about the same time as the preceding and 

 is also very common and now widely distributed. Its nests of the usual leaf-formation 

 are often found in houses in holes or crevices, e.g. between the slats of window blinds. 

 They have been found in large numbers concealed in leaves of various palm trees, 

 which had been rolled and spun together by the caterpillars of Omiodes blackburni, an 

 injurious Pyralid moth. It visits many kinds of flowers, cultivated and other. 



A still more recent importation, at present found only on Oahu, is a species of 



Lithurgus'^, which was first noticed in some numbers in 1900. It is locally abundant 



and widely distributed over this island. In some remarks that I published elsewhere 



on this species I stated that the labial palpi were four-jointed, in error, for there are but 



' Determined for nie by Prof. Cockerell as Z. albofimbriaius^ found in Tahiti. Probably an introduction 

 into both countries from the Oriental region, whence I have seen forms hardly different. 



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