E. T. CRESSON, JR. 39 



COSTA RICAN DIPTERA 



COLLECTED BY PHILIP P. CALVERT, PH.D., 1909-1910 



Paper 3. — A Report on the Ephydridae 



BY E. T. CRESSOX, JR. 



The general introductory remarks relative to this series already 

 have been given, and will be found in the first paper.^ Included in 

 that introduction is a list of the localities where the material was 

 collected, prepared by Dr. Calvert, consisting of brief descriptions 

 of the topography and the general surrounding conditions of the 

 localities visited.- Dr. Calvert collected this material between 

 May 14, 1909 and May 1, 1910. 



The present paper treats of the species of the acalyptrate 

 family Ephydridae. The material is especially rich in this group, 

 comprising over one hundred and thirty specimens, representing 

 twenty-eight genera and fifty-seven species. Two new genera 

 and twenty-two new species are introduced and described. The 

 species of this family are most easily collected by sweeping, espe- 

 cially near and over mud or water which may be in stagnant or 

 fresh pools, in running brooks or at the shores of creeks, rivers or 

 oceans. Rarely are they found in pasture or dry woods. . It is 

 the endeavor of the writer, in this paper, to present a preliminarj^ 

 synopsis of, or a guide to, the species of this group of Diptera 

 that may be found in Costa Rica. The work is by no means 

 exhaustive in its treatment of the ephydrid fauna, for it will take 

 much more thorough collecting than Dr. Calvert was able to do, 

 to give us anywhere near the number of species which occur in 

 that region so rich in its insect fauna. The types of the new 

 species are in the collection of the Academy of Natural Sciences 

 of Philadelphia. 



The engagement of the author in a revisionary study of the 

 Ephydridae of North and South America, makes it possible for 

 him to offer this paper in its i)rescnt foi'ni. I'rior to this writing 



1 Trans. Am. Ent. Soc, xl, p. 1, 1914. 



2 A full account of Dr. Calvert's sojourn in Costa Rica is published by The 

 Maomillan Company, New York, "A Year of Costa Rican Natural History" 

 by A. 8. & P. P. Calvert, and full notes on his collecting may be found therein. 



TRANS. AM. ENT. SOC, XLIV. 



