Smith. — Notes on New Zealand Earth-tvorms. 185 



their burrows in prodigious numbers, and move about on the 

 surface ; some are in search of food ; some to pair ; while others 

 seek new ground to burrow afresh. The nights they appear on 

 the surface, the weka and swamp-hen commit great havoc among 

 them. In some parts of the "Waiareka Valley, near Oamaru, 

 the land is intensely adhesive ; if ploughed when a little wet, it 

 adheres to the plates of the plough and causes it to stick fast in 

 the furrow. In this particular mould this large species exists 

 in enormous numbers, and attains a great size. From the 

 adhesive nature of the mould, the castings they eject retain 

 their size and form for a long time, and are not so easily defaced 

 or washed away by heavy rains as those thrown up on friable 

 loam. Some thrown up by the larger worms resemble the one 

 figured by Mr. Darwin,* but not so large or perfect. I have not 

 seen an analysis of this mould, but after experimenting with a 

 number of the worms, by handling the animals with the bare 

 hand, and mixing the secretions with the other soils, I am of 

 opinion that its tenacity is chiefly owing to its being saturated 

 with the intestinal secretions of these animals. The same 

 result is obtained by placing a number in a large flower-pot 

 containing friable loam ; in a few months it is changed to a 

 rich adhesive mould. The land, however, is well suited for 

 growing wheat, a yield of 70 to 80 bushels per acre being 

 commonly obtained on it. As winter approaches, any castings 

 standing up are soon pulverized by frost, and form small heaps 

 of fine mould on the surface. 



Acanthodriliis, sp. nov. 

 This undescribed species is the largest yet discovered, and 

 although I have stated that it varies in size and colour in 

 different localities, individuals are met with much larger than 

 the largest forms of A. uliginosus. It is found living chiefly in 

 clay, or clayey soils, and its habits are more sluggish than the 

 last-named species. It is limited in its range, being confined 

 to a few places in the districts I have examined. In one spot, 

 a few miles below the Eangitata Gorge, the largest forms are 

 found. Its colour in this locality is reddish-pink. It also 

 occurs in a few places on the Canterbury Plains, At Oamaru 

 I find it in one place, a small swampy patch of Native land ; 

 but here it exists as a more diminutive species, and never 

 attains the size of those living in the two other localities. Its 

 burrows are pecuhar, as they are more commonly found running 

 horizontally, than perpendicularly or obhquely. They appear 

 to burrow in this manner when inhabiting solid clay. The 

 burrows are of no particular form, but wind in all directions, 

 generally horizontally, and near the surface, especially if the 

 clay be wet. 



• " Vegetable Mould," p. 129. 



