HOUSE-MARTINS. 197 



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

 tipulcK (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 entertain- 

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

 and new field in natural history. 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 conse- 

 quently very prolific. I am, &c. 



LETTER XXXVI. To THE HON. DAINES BARRINGTON 



DEAR SIR, Selborne, Nov. 22, 1777. 



You cannot but remember that the twenty-sixth and twenty- 

 seventh of last March were very hot days ; so sultry that every 

 body complained and were restless under those sensations to 

 which they had not been reconciled by gradual approaches. 



This sudden summer-like heat was attended by many summer 

 coincidences ; for on those two days the thermometer rose to 

 sixty-six in the shade ; many species of insects revived and came 

 forth; some bees swarmed in this neighbourhood; the old 

 tortoise, near Lewes in Sussex, awakened and came forth out of 

 its dormitory ; and, what is most to my present purpose, many 

 house-swallows appeared and were very alert in many places, and 

 particularly at Cobham, in Surrey. 



But as that short warm period was succeeded as well as pre- 

 ceded by harsh severe weather, with frequent frosts and ice, and 

 cutting winds, the insects withdrew, the tortoise retired again 

 into the ground, and the swallows were seen no more until the 

 tenth of April, when, the rigour of the spring abating, a softer 

 season began to prevail. 



Again ; it appears by my journals for many years past, that 



* 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 



