The Natural History of Selborne 285 



their excrement, is a fine manure for grain and grass. Worms pro- 

 bably provide new soil for hills and slopes where the rain washes the 

 earth away ; and they affect slopes, probably to avoid being flooded. 1 

 Gardeners and farmers express their detestation of worms ; the 

 former because they render their walks unsightly, and make them 

 much work ; and the latter because, as they think, worms eat their 

 green corn. But these men would find that the earth without 

 worms would soon become cold, hard-bound, and void of fermenta- 

 tion, and consequently sterile ; and, besides, in favour of worms, it 

 should be hinted that green corn, plants, and flowers, are not so 

 much injured by them as by many species of coleoptera (scarabs), and 

 tipulse (long-legs) in their larva, or grub-state ; and by unnoticed 

 myriads of small shell-less snails, called slugs, which silently and 

 imperceptibly make amazing havoc in the field and garden.* 



These hints we think proper to throw out in order to set the 

 inquisitive and discerning to work. 



A good monography of worms would afford much entertainment 

 and information at the same time, and would open a large and new 

 field in natural history. 2 Worms work most in the spring ; but by 

 no means lie torpid in the dead months : are out every mild night 

 in the winter, as any person may be convinced that will take the 

 pains to examine his grass-plots with a candle ; are hermaphrodites, 

 and much addicted to venery, and consequently very prolific. 



I am, &c. 



* Farmer Young, of Norton Farm, says, that this spring (1777) about four 

 acres of his wheat in one field was entirely destroyed by slugs, which swarmed on 

 the blades of corn, and devoured it as fast as it sprang. 



1 This very interesting passage gives in brief, but without any full detail of 

 experiments or observations, the main principles afterwards so fully worked out by 

 Darwin in his wonderful treatise on Vegetable Mould and Earthworms. Oddly 

 enough, Darwin, by a rare slip of memory in so candid and accurate a writer, does 

 not allude in his treatise to this passage, from which he must almost certainly have 

 derived the first impetus towards his long and patient investigation of the 

 subject. ED. a The "monography" here desired has since been amply 



supplied by Darwin. ED. 



