Chap. IV. OF ANCIENT BUIIiDINGS. 185 



and by suddenly lifting up the little cakes of 

 earth, four worms were seen in the act 

 of quickly retreating. Two castings were 

 thrown up during the third night on the 

 floor, and these were of large size. The 

 season was not favourable for the full activity 

 of worms, and the weather had lately been 

 hot and dry, so that most of the worms now 

 lived at a considerable depth. In digging 

 the two trenches many open burrows and 

 some worms were encountered at between 

 30 and 40 inches beneath the surface ; but at 

 a greater depth they became rare. One 

 worm, however, was cut through at 48 1, and 

 another at 51^ inches beneath the surface. 

 A fresh humus-lined burrow was also met 

 with at a depth of 57 and another at 65^ 

 inches. At greater depths than this, neither 

 burrows nor worms were seen. 



As I wished to learn how many worms 

 lived beneath the floor of the atrium — a 

 space of about 14 by 9 feet — Mr, Farrer 

 •was so kind as to make observations for 

 me, during the next seven weeks, by which 

 time the worms in the surrounding country 

 were in full activity, and were work- 



