270 Transactions. — Zoology. 



equally favourable, did not differ from those taken in this field at the same 

 time, it may be fairly assumed that if fresh tests had been made with 

 equal care, the results would have been as great. As far as my expe- 

 rience goes, worms seem to be, as a rule, less numerous in worked ground. 

 This does not appear to be the opinion of other observers. Iu an orchard, 

 originally grass land and favourable for worms, but kept ploughed the last 

 four years, the average was 12 worms per square foot. Several acres in 

 another orchard, light, deep, dry soil, formerly in grass, only averaged 2J. 

 The number of worms found in garden ground varies considerably ; in the 

 drier portions they are often scarce, but in the moist and shady places they 

 are numerous, especially large worms (L. uliginosus) weighing 27-30 grains. 



Prom this it appears that worms abound in most cultivated lands in 

 New Zealand ; earth-worms are also numerous in moist open spaces be- 

 neath high manuka (Leptospermum) ; they affect the edges of swamps in 

 considerable numbers, spreading backwards year by year up the ridges, 

 when the conditions are favourable, largely contributing to form the good 

 soil often found there. Under furze, dense manuka and Pomaderris, if the 

 soil is dry, worms are scarce. In fern lands they are rare, except in the 

 damp open spaces, or half-dry swamps covered with dwarf manuka, from 

 whence they spread upon the land being cultivated. I have not had the 

 opportunity of observing native grass lands during the wet season, but from 

 the work done they seem to be fairly represented in some places. 



The length of time that land of this class — i.e., fern land — takes to be- 

 come stocked with worms when laid down in pasture, of course depends 

 upon the extent, moisture, and surroundings. Fields of no great area in 

 the vicinity of older cultivations and swamps appear to get well stocked in 

 about fifteen years. In a portion of a 100-acre field laid down in pasture 

 ten years ago the average of the tests was equal to those given above, but 

 the conditions were extremely favourable. In the remoter portion sown 

 two years later, although increasing, worms are still scarce. 



It is unnecessary to enter to any extent into the amount and value of 

 the work done by earth-worms, as the subject has been ably discussed by 

 our illustrious master ; but it may be of interest to describe a section I ob- 

 served when forming an orchard in October, 1875. The vegetation burnt 

 off the newly-cleared land — a raised beach, Manukau Harbour — consisted 

 mostly of manuka and flax, apparently the growth of about thirty years. 

 The trench opened in digging the ground exposed a section consisting of 

 about 4£ inches of black mould, and a horizontal layer, nearly 1 inch thick, 

 of wood-ashes, burnt clay, small stones, and fragments of pumice, lying on 

 a brownish-green arenaceous clay. The black mould was perfectly free 

 from stones, etc., and when a spit was taken up it readily split off from the 



