Chap. I. SITES INHABITED. 9 



Eisen ;* but two of these rarely burrow in the 

 ground, and one inhabits very wet places or 

 even lives under the water. We are here 

 concerned only with the kinds which bring 

 up earth to the surface in the form of cast- 

 ings. Hoffmeister says that the species in 

 Germany are not well known, but gives the 

 same number as Eisen, together with some 

 strongly marked varieties.*)* 



Earth-worms abound in England in many 

 different stations. Their castings may be 

 seen in extraordinary numbers on commons 

 and chalk-downs, so as almost to cover the 

 whole surface, where the soil is poor and the 

 grass short and thin. But they are almost or 

 quite as numerous in some of the London 

 parks, where the grass grows well and the 

 soil appears rich. Even on the same field 

 worms are much more frequent in some places 

 than in others, without any visible difference 

 in the nature of the soil. They abound in 

 paved court-yards close to houses ; and an 

 instance will be given in which they had 



* ' Bidrag till Skandinaviens Oligochajtfauna,' 1871. 

 t ' Die bis jetzt bekannten Arten aus der Familie der Eegen- 

 wtirmer ' 1845. 



