Ixxxii FAUNA HAWAIIENSIS 



N. crabronoides well illustrates this point. Originally, with difficulty, I obtained a 

 few females, and on various other occasions at the same place and time of year 

 failed to find even one. Yet on another occasion, also at the same season, I observed 

 many scores in a few hours in this same spot. Similar instances have frequently been 

 noticed, and a species which is abundant one year in the summer months may on 

 another occasion appear at quite a different season in the same locality. It is in 

 some respects rather interesting to note that the Hawaiian Nesoprosopis most nearly 

 allied to the one apodemic species are the littoral species of the N. blackbzirni group, 

 while the forest-frequenting forms include those most extremely divergent from these. 



Comparatively few of the species are distributed over many of the islands of the 

 group, but N. facilis and difficilis are found on all the islands excepting Kauai, where 

 the former is represented by an extremely closely allied form, and N. laeta occurs on 

 all. Several species are common to the three neighbouring islands Lanai, Maui and 

 Molokai. Many are peculiar to a single island and further investigation is not likely 

 to prove this incorrect in the case of a good many species. Thus N. setosifrons is 

 represented on Oahu by N. anomala and on Kauai by N. perspiaia, while at present 

 no corresponding form has occurred on the other islands. N. insignis of Hawaii is 

 represented on the three intermediate islands by N. satelles, and probably on Kauai 

 by AT. andrenoides, while no corresponding form has so far been found on Oahu. The 

 N. dunietorum group has an allied species peculiar to each island, excepting Oahu and 

 Molokai. 



As far as our present knowledge goes, the endemicity of the species as regards 

 islands is as follows: Hawaii has iS species endemic, Maui 6, Molokai i, Lanai i, 

 Oahu 3, Kauai 8. It is clear that the interchange of species between the three 

 neighbouring intermediate islands is much easier than between others of the group, 

 although Maui, a large island, with great variety of natural conditions, contains six 

 endemic species. If we treat these three islands as one we find that together they 

 have 13 that are not found on other islands, each in fact being well endowed with 

 species of the genus. Thus the small island of Lanai has no less than 14 species, 

 while but one is endemic, and even that one is likely to be found on Molokai. 

 Oahu seems to be poor in its Prosopid fauna, only 1 1 species being at present 

 known (or three less than on little Lanai), but of these three are endemic. Kauai 

 is poorest of all in number of species, only nine being known, but eight of these 

 are endemic. Hawaii stands alone in the richness of its species, which number 24, 

 and no less than 18 are endemic. These figures no doubt are subject to slight 

 alteration, for in one or two cases species described as distinct in Vol. I, pt. i of 

 this work are likely to be sunk, as being merely varieties. I should add that since 

 this part was published several species have been found to have a wider distribution 

 than is indicated therein, and in the figures given above these new localities have 

 been taken into consideration. 



