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* Ruricola ' has given us of these destructive pests. Four 

 years ago (1902) there was an alarming plague of the larvae 

 on the golf links in the marshes of the Dee, Cheshire. It was 

 on this occasion that the writer had exceptional opportunities 

 of observing the habits of these insects, and some facts then 

 gleaned may at least prove of interest if not instructive. It 

 should be clearly understood, however, that there are at least 

 three species of crane flies which are destructive to crops and 

 plants of various kinds, and also that the larvae of all of them 

 are popularly known as • leather jackets/ The following facts, 

 however, concern one species only, Tipula oleracea, one of the 

 largest and most familiar of the family : — 



" The infested area under observation extended over several 

 hundred acres, covering practically the whole of the grass land 

 of the marshes, a great portion of which is perpetually grazed 

 by sheep, the remainder being reserved for the use of the golf 

 club. It was on the ground of the latter that the observations 

 were chiefly made. The unmown grass on the links is generally 

 short, and amongst it grows patches of White Clover, with 

 here and there tufts of the Sea Pink (Armeria maritimd) and 

 other less common plants. Almost every square yard of grass 

 was injured more especially so in the shallow depressions and 

 deeper hollows. In these the grass was so completely destroyed 

 that there was not a green blade left, and the dead brown 

 patches extended in every direction over the whole of the land. 

 So effectually had the ' leather jackets ' severed the crowns 

 of the plants that one could, with little difficulty, roll back the 

 turf into large masses, leaving the ground smooth and bare, 

 exposing the surface-tracks of the larvae. Strange to say, the 

 White Clover and the Thrift were left intact and uninjured, 

 and large patches and isolated plants of the former were 

 growing amidst and through the dead grass which had been 

 severed from its roots. On exposing the bare ground one also 

 succeeded in occasionally disinterring a ' leather jacket,' but 

 such instances were rare. By carefully skimming off a thin 

 layer of soil one immediately exposed to view innumerable 

 burrows large enough to admit an ordinary-sized slate pencil. 

 In these the larvae were discovered, and by making a vertical 

 section of the burrows one also found that each larva had 

 excavated for itself a separate J -shaped dwelling into which 



