78 



Cercyon Uttoralis, Gyll. 

 C. depressiis, Steph. 

 Heteroceriis inarginatus. 



Bose. 

 Li/nuiaeiiiii n'Kjropiceuni, 



Marsh. 

 Cillemis lateralis Sam. 

 Treehina lapidosus, Daws. 

 Bemhidinm convinnum, 



Putz. 

 B. ephippiinn, Marsh. 

 Aepus marinns, Stroem. 

 A. Bohi)i}i, Lab. 

 Micralymma bn'ripeunf, 



Gyll. 



TrogopJilof'Ks anglicanus, 



Sharp. 

 Mynnffopova (Xen Jisa) 



urida, Er. 

 M. sulcata, Kies. 

 Cafms cicatricosus, Er. 

 C. xanthnloma, Grav. 



C. sericcus, Holme. 

 C.fitcicola, Curtis. 



A ctocharis Beadingil. 



Sharp. 

 Phytosus spiuiffr Curtis. 

 P. halticKs, Kraatz, 

 P. nigrirentiis, Chev. 

 Diglossa mcrsa, Hal. 



D. silmaticolUs, Rey 



DiPTERA. 



A marked feature among marine flies is tlie reduction 

 or total atrophy of the wings. The first stage in the 

 reduction is seen in Chersodromia arenaria, where the 

 wings are much shortened so as to be of very little service 

 in flight. This is carried a step further in a Southern 

 France species, P samathiomya pedinata, Derby, in which 

 the wings have become greatly narrowed and strap-like, 

 and the nervures atrophied ; a similar condition is seen 

 in a Californian marine fly, Eretmoptera Browni, Kellogg. 

 An extreme case occurs in the females of the genus 

 CJitnio, Avhere the wings have disappeared completely, 

 although in the males they are tolerably well developed. 



This reduction of the wings has been explained as 

 being an advantageous condition, since it prevents the 

 insects from being blown out to sea. A similar explana- 



