21 
son which I experienced, the mercury seldom fell a degree or 
two below 70° F., and in the warm season rose to over “90° F 
At no time, therefore, can the weather, at low levels, be termed 
cold—though the natives themselves will not agree with you on 
this point—but while flowers and fruits of one sort or another 
may be found throughout the year, there is a relative scarcity of 
insect life during the less warm and dryer months, just as occurs 
in temperate regions in a much more pronounced degree, and 1f 
we investigate, it will be found that many insects suspend their 
activities for a time and hibernate or aestivate as elsewhere. 
For the study of insect life the tropics offer decided advan- 
tages over the temperate regions; in the former the life-cycles of 
insects are generally more rapid and in many cases uninterrupted 
throughout the year. Insects are more numerous, many are of 
greater size, and the climate, while not always most salubrious, 
seldom interrupts entomological enterprise. Cloudy weather, or 
even at times a light rain in the tropics does not spell a cessation 
of insect activities. 
I have derived much information from the works of other 
entomologists, and it will be found that related wasps of temper- 
ate and tropical regions have much the same habits. Those who 
would gain a better idea of the habits of wasps will do well to 
consult “Fabre’ s Souvenirs Entomologiques, a large part of which 
has been translated into English; Peckhams’ Social and Solitary 
Wasps; Latter’s Bees and Wasps; Hartman’s Observations on 
Some Solitary Wasps of Texas; Ashmead’s Habits of Aculeate 
Hymenoptera ; Dutt, on Life Histories of Indian Insects; Sharp, 
in the Cambridge Natural History of Insects, V, Pt. 2; Maindron, 
Notes pour servir a Vhistoire des Hymenopterés de l’Archipel 
Indien et de la Nouvelle Guinée; Howes, in Tropical Wild Life 
in British Guiana; Isely’s Biology of Some Kansas Eumenidae ; 
Bequaert’s Revision of the Vespidae of the Belgian Congo; and 
Rau & Rau, Wasp Studies Afield. 
I owe special thanks to Mr. F. Lutz of the American Museum 
of Natural pes New York, for copying literature inacces- 
sible to me; to Mr. S. A. Rohwer of the United States National 
Museum, for identifying a number of the wasps considered here; 
and he has kindly consented to publish his paper as a part of this 
Bulletin; to Mr. Nathan Banks of Cambridge, Mass., for spider 
determinations; to Mr. J. A. G. Rehn of Philadelphia, for naming 
Orthoptera; to Mr. J. C. Bridwell, for information and criticism ; 
to Mr. W. R. R. Potter, illustrator for the Experiment Station 
here, for valuable hints on drawings, many of the latter being his 
own work; to Mr. O. H. Swezey for proof-reading, etc.; and to 
Prof. C. F. Baker, Dean of the College of Agriculture, P. I. 
The types of the species described by me are all in the collection 
of the H. S. P. A. Experiment Station, Honolulu. 
