HYMENOPTERA 7 



one another. It might be supposed that the local peculiarities of coloration have 

 a protective value, but as I have pointed out in the Proceedings of the Cambridge 

 Philosophical Society all the .evidence is opposed to this view. 



Another noteworthy point about the endemic aculeates is the general feebleness 

 of their sculpture. Of the large number "of species of Odynei-iis there are certainly 

 a good many in which the puncturation is strong and even coarse, but in many it is 

 very feeble or nearly entirely effaced. The bees are nearly all remarkable for their 

 fine and shallow puncturation, as also are the Mimesidae, while in the Crabronidae 

 the general tendency is to effacement of the sculpture. 



The literature relating to the Hawaiian aculeata is as follows: — 



Fabricius, Eiit. Syst. 11. p. 269. 



De Saussure, Etud. fani. Vesp. iii. Mon. Masar. et Suppl. p. 289. 



Smith, Cat. Hym. Ins. i. p. 23. Id. op. cit. iv. p. 421. 



Holmgren, Eugenies Resa, Zool. vi. p. 441. 



Smith, J. Linn. Soc. xiv. pp. 674 — 6S5. 



Blackburn and Kirby, Ent. Mo. Mag. xvii. pp. 85 — 89. 



Cameron, Trans. Ent. Soc. 1881, p. 562. 



Blackburn and Cameron, P. Manchester Soc. xxv. (Session 1885 — 86), pp. 

 134—176. 



Dalla Torre, Wien. Ent. Zeitg. viii. {1889), p. 124 et seq. (also Cat. Hym. 

 Ins. passim). 



Perkins, Pj'oc. Phil. Soc. Cambridge, Vol. ix. Part vii. (1897), p. 378. 



Altken, Ent. Nachr. xxiv. (1898), p. 340. 



§ 2. Systematic account of the Hymenoptera Aculeata, 



FOSSORES. 



The Fossorial Hymenoptera of the islands are represented by only six genera, 

 and of these probably two have no place in the autochthonous fauna. All the 

 genera belong to that section, which comprises the insects with short prothoraces, and 

 they represent four distinct sub-families. The truly endemic species however belong 

 entirely to the Mimesidae and Crabronidae, and all prey on Dipterous insects; the 

 members of the former family, so far as I have observed, provisioning their cells 

 invariably with species of Tipulidae, while those of the latter prey not only on 

 these, but also on other Flies. In some cases at any rate a species of Crabro will 

 take Flies of very different species, by no means confining its attention to the 

 capture of one particular kind. Some of the species of this genus are very 

 abundant, and may sometimes be seen in great numbers around a dead animal, to 

 which they are attracted by the abundance of their prey. 



