702 CHARLES PAUL ALEXANDER 



A permanent series of the immature stages of the species studied has 

 been carefully preserved in the writer's collection, while additional material 

 has been placed in the principal collections of the United States. A series 

 of two hundred and seventy microscope slides showing details of structure 

 of the larvae and the pupae has been prepared, representing some seventy 

 species arranged in forty genera. The typical larvae and pupae 

 (nepionotypes and neanotypes) have been designated and preserved in 

 alcohol for future reference. 



For the most part, the life histories discussed in this paper have not 

 been described hitherto. Besides the reared material, the writer has in 

 his collection a very large number of unknown larvae and pupae, many 

 of them representing interesting and un described types. In this paper 

 but three or four of these are considered, and these only because they 

 introduce new features of organization (Eriopterine No. 1, Tipulini No. 

 1 and No. 2). 



A vast amount of work remains to be done on the immature stages 

 of crane-flies. Exact, detailed life histories of individual genera and 

 species are especially needed and the reward for effort will undoubtedly 

 be great. Nothing is known of the tropical and the antipodal faunas, 

 and their life histories will probably be unraveled but slowly, due to the 

 inaccessibility of most of the regions. 



The majority of specimens studied in the preparation of this paper 

 were reared by the writer during the past nine years. Many specimens 

 were received from various sources, however, including many of the most 

 desirable life histories, and these are herewith gratefully acknowledged: 



Dr. James G. Needham, Ithaca, New York. The extensive collections received from Dr. 

 Needham include the material described in the various Adirondack reports, as well as 

 numerous previously unrecorded specimens. In addition, the writer has accompanied 

 Dr. Needham on many of his field trips in quest of the immature stages of aquatic insects, 

 and has received much encouragement and inspiration from this association. 



Charles W. Johnson, Boston, Massachusetts. Immature stages of Aeshnasoma, Elephant- 

 omyia, Teucholabis, and other species. 



The late Frederick Knab, Washington, D. C. Immature stages of Rhipidia bryanti, 

 Elephantomyia, Epiphragma solatrix, and other species. 



J. A. Hyslop, Hagerstown, Maryland. Longurio (larvae), Oropeza, Gnophomyia. 



J. R. Malloch, Urbana, Illinois. Rhipidia bryanti. 



C. T. Greene, Washington, D. C. Protoplasa (supposition). 



H. L. Viereck, Washington, D. C. Protoplasa (supposition). 



W. L. McAtee, Washington, D. C. Protoplasa (supposition); numerous larvae from the 

 Pribilof Islands. 



William Lundbeck, Copenhagen, Denmark. Helobia and other species. 



Dr. C. Wesenberg-Lund, Hillerod, Denmark. Phalacrocera, Ptychoptera paludosa, Tipula 

 maxima, and other species. 



