290 



THE BIOLOGY OF INSECTS 



The assemblages of Clunio can be observed only during 

 the low spring tides, when the rocks on which they live are 

 exposed twice daily for a week or so. The males skim, as 

 already mentioned, over the surface of the tidal pools ; they 

 also crawl on the masses of the bright green seaweed 

 Cladophora, where the wingless females creep and on which 

 the larvae feed. M. Bezzi (1913) has given an account of 

 the four species of Clunio known from the Atlantic, Channel, 

 and Mediterranean coasts. When pairing takes place, the 

 male seizes his mate by means of his powerful claspers, 



Fig. 72. — Chironomid Midge {Clunio marinus), British and Irish 

 coasts, a, male (side view) ; b, female (ventral view) ; c, larva (side view), 

 X 20. After Carpenter {Knowledge, xxiv, 1901). 



holding her so that her elongate body is in a line with his 

 own, her feet clear of the surface whereon he walks, kicking 

 in the air. After half an hour's promenade the male releases 

 the female, who proceeds to lay her eggs, fifty to over a 

 hundred in number, enclosed like those of Chironomus 

 in a cylindrical gelatinous tube which is attached to rock or 

 seaweed. Chevrel has given a picturesque account of the 

 egg-laying process and its sequel. '* When the operation 

 is finished the female, exhausted by the efforts which she 

 has made, can only move slowly, she walks painfully, stops 



