HEMIPTERA 97 



hawaiiensis Kirk, and Daclera punctata Sign, (the latter from Reunion), are extremely 

 alike ; the latter genus has another species D. rufcscens Stal, from Australia, with 

 which, unfortunately, I am not acquainted. 



On studying the records of localities mentioned under each species, it will be noted 

 that very few species are found under 1000 ft., most being from 2000 — 4500 ft. The 

 reason of this is that the low-lying parts of the Islands have been for a long period 

 under cultivation, so that almost invariably it is only from the higher elevations that it 

 is possible to obtain specimens. It will not be long belore the doom of the last of the 

 precinctive fauna is fulfilled, for Dr Sharp informs the writer that many of the insects 

 lately collected by j\lr Perkins have been rescued from the jaws of ants. A curious 

 confirmation of this is before me in the person of an individual of Mctrarga villosa 

 which has an ant clinging to one of the antennae by means of its mandibles. I have 

 gathered together all the informations possible relating to habits, food-plants, etc., 

 but it is greatly to be regretted that these are so meagre ; information as to the 

 metamorphoses and habits of Metrarga, Piendoi'eclada, and Sarona would be of the 

 highest interest, but it is to be feared that this is now for ever lost to us. 



The variability of the Hawaiian Rhynchota is, as before remarked, most e.xtra- 

 ordinary. Writers on the other orders have regarded this Fauna as composed of few 

 genera, many of these however containing a large, sometimes very large, assemblage of 

 species, with however tew individuals for each species. Dr Sharp notes Plagithniysiis 

 with 29 closely allied but mostly quite distinct forms, and these forms are in general 

 each found only in one island. Mr Perkins records Oodcmas with 46, Proterhinus 

 with 122!, and A^esoprosopis with 32. I\Ir Grimshaw describes 40 of Drosophila, 

 Mr Meyrick '^'] Scopariac, and Mr Sykes 76 Leptachatinae, loi Amastrae, and 

 107 Achatinella. 1 can only say that after the most exhaustive study, I cannot achieve 

 anything like these results. Whether it be due to a constitution in the Rhynchota 

 differing from that of other orders I cannot say ; I can only see a large assem- 

 blage of forms varying in the most bewildering fashion, forming incipient species, 

 if one will, but at the same time forming links of such a character that it seems 

 unreasonable to attempt the arbitrary definition of many "species." These variations 

 are not confined to any particular island in each case but are scattered throughout 

 the archipelago. 



The genital appendages, upon which great stress — in many cases no doubt 

 correctly — is laid, vary considerably in certain instances ; naturally, little variation is 

 to be expected in the case of purely chitinose clasps or hooks ; on the other hand the 

 circumambient parts are mostly feebly chitinized (in the smaller forms) and appear to be 

 very liable to post-mortem distortion, so much so that I have not felt it expedient to 

 work out the genital differentia (if indeed these are notable) in the Cixiaria etc., in the 

 absence of freshly killed or alcoholic material. 



Although I may be mistaken I feel convinced that the careful breeding ab ovo of 



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