NOTES ON THE CRANE-FLIES OF THE HAWAIIAN 

 ISLANDS (Tipulidae, Diptera). 



By Charles P. Alexander, Urbana, Illinois. 



During the past few years some extensive collections of 

 Hawaiian crane-flies have been received from Dr. James F. 

 Illingworth and Mr. O. H. Swezey, to both of whom I am 

 indebted for many favors. The records of these collections, 

 together with a few additional specimens from other sources, 

 are herein recorded to supplement our scanty knowledge of 

 the Hawaiian Tipulidae. A few general statements of the 

 faunal constituents may be given. 



As might be expected, the crane-fly fauna of the Islands 

 is strongly endemic. The dominant genus is Dicrmiomyia 

 with about a dozen species, all of which are apparently con- 

 fined to the Islands. The remaining genera, Libnotes, Sty- 

 ringoniyia, Gonomyia and Trimicra, are represented each by a 

 single species, all, with the exception of Styringomyia didyma, 

 apparently being endemic. This last mentioned species breeds 

 in decaying organic matter, such as manure, and has probably 

 been spread over the Australasian islands through the agency 

 of man. The entire lack of the larger, vigorous Tipuline forms 

 is striking, but entirely in agreement with the fauna of many 

 other oceanic islands, where the Tipulinae are entirely lacking 

 and the dominant genera are Dicranomyia and related groups, 

 (Seychelles, Guam, Fiji, etc.) 



The following transcription of a letter received from Dr. 

 Illingworth will give a clear idea of the conditions under which 

 Hawaiian crane-flies are found. Under date of March 6, 1917, 

 he writes as follows: 



"Last week end I spent in the Waianae Mountains, which are at 

 the far end of the Island. The range is much older than the mountains 

 near Honolulu (Koolau) and the native insect fauna appears to be more 

 abundant. 



"I have never seen crane-flies more abundant, but I fear they 

 belong to a few species. I followed along the stream which had many 

 falls — every wet cavern was filled with them. I tried sweeping the 

 grass along the banks but with no success. One only gets crane-flies 

 in the mountains here and it is a rather difficult matter to get to the 

 places where they are abundant. One or two common species come to 

 the lamps in the low lands — these I have sent before." 



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