228 DIPTERA OR TRUE FLIES. 



in the soil and on the grass near some plants — the greater the 

 shelter the more they frequent it, hence we find these pests 

 always most frequent in permanent pastures. They prefer 

 damp spots to oviposit — in fact, most Tipulidse frequent damp 

 and swampy places, some larvae living in water, even in brine 

 pools. The black ova of the crane-fly soon hatch out into the 

 larvsB. The adults appear twice a-year, one brood in the spring 

 and early summer, the second in the autumn. The larvae of 

 the second brood live through the winter, and pupate in the 

 summer. The majority hatch out in the autumn. The grubs 

 are called "Leather-jackets" (fig. 124, 4), on account of their 

 tough skin, which is brown and wrinkled. They have a blunt 

 anal extremity, which has a few finger-like processes on it. 

 The roots of practically all plants are attacked by them, and 

 are so eaten away as to kill the plant. The pupae are brown 

 (fig. 124, 5), and provided with circles of spines; the head has 

 two curved horns (palp cases). We find them in the ground, 

 forcing their way up when ready to emerge by means of the 

 spines, until half the pupal case projects out of the earth, when 

 the shell splits and the fly emerges, .soon to deposit fresh ova. 

 Other species, as the Spotted Crane-fly {Pachyrhina maculosa, 

 Tipula paludoM, T. lateralis), also cause loss. 



Prevention awl Remedies. — Gas-lime is very injurious to these 

 grubs, and may be well employed on land when it is infested 

 with " Leather-jackets." It is especially valuable put upon 

 mould and leaf-heaps, where crane-flies lay their eggs abun- 

 dantly, as a preventive of oviposition. The drainage of damp 

 land often checks their presence. Brush-harrowing grass land 

 when we see the flies about is advantageous, as it disturbs and 

 crushes the eggs laid by the female. It is said that the lar\ » 

 come out on to the surface at night, and that rolling with a 

 Cambridge ring-roller then does much good by crushing them. 

 Vaporite I have found fatal to them. Birds are the great 

 natural check of this pest, those that are beneficial being 

 mentioned in another chapter. 



