ADAPTATIONS TO HAUNTS AND SEASONS 289 



and in ball-like masses on the water." On Kerguelen, 

 Eaton found females of a tiny midge (Halirytus amphibius) 

 with short feelers, slender legs, elongate body, and wings 

 reduced to the smallest vestiges. These frail creatures 

 live " at the verge of the tide, creeping over Enteromorpha 

 and mussels exposed by the recess of the sea and walking 

 on the surface of the puddles and tide-pools." Eaton 

 observed the midges crowded *' on small isolated rocks 

 always submerged at high water," and suggests that when 

 the receding tide leaves these rocks bare, ** all the flies hurry 

 up from below to take an airing." 



A little midge, Clunio marinus^ which haunts the tidal 

 margins of the Irish, British, and French coasts, does not 

 yield in interest to its relations in remote quarters of the 

 globe. The male was described by A. H. Haliday (1858), 

 who found numerous specimens in Kerry " on gravelly 

 sea-coasts below high- water mark, walking with the wings 

 half raised and in rapid vibration without taking flight." 

 The wings, indeed, though relatively broad and well- 

 proportioned, are short in comparison with the insect's 

 somewhat massive abdomen, and serve as sails rather than 

 organs of flight ; the little midges with their elevated wings 

 skim over the surface of the rock pools. A. D. Imms 

 (1903), however, describing the habits of C. hicolor on the 

 coast of the Isle of Man, states that the male flies " short 

 distances at a time, generally about two feet," and that 

 it skims over the water and rocks within a few inchesof the 

 surface. The thorax of the male (Fig. 72, a) is large and 

 hood-like, protecting the retracted head with its small eyes, 

 the cornea of each composed of few oval facets. The jaws 

 are so reduced that the midges in the adult state can take 

 no food and their lives must be very short. The female of 

 Clunio was discovered and described independently by 

 R. Chevrel and G. H. Carpenter (1894) on the French and 

 Irish Channel coasts in C hicolor and C. marinus respec- 

 tively. She is a wingless and degraded insect, with elongate 

 hind-body, short and feeble legs, a small head bearing 

 feelers with few segments, and very reduced eyes (Fig. 72, h), 



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