AN OLIGOCH^TE WORM. 301 



Goodrich (7) gives a good description of the nephridia and 

 coelomic corpuscles of a species of Enchytrceus, but says very little 

 about any other organs. 



The Enchytraeids are amphibious in their habits. They may 

 be found in comparatively dry places, as in soil or leaf-mould ; 

 but they are also found in certain places where they are practically 

 living an aquatic mode of life. A common resort of these Enchy- 

 trasids is on the sea-shore, but when found here they are most 

 abundant at the point where fresh water is running into the sea. 

 Consequently, they are not purely land or aquatic animals, nor 

 yet are they purely fresh-water or marine. 



The Enchytraeids or " white worms '" have been found in recent 

 years to be much more plentiful than was formerly supposed. 

 They are found most abundantly wherever there is decaying 

 vegetable matter, such as in leaf-mould, dead and decaying plants, 

 etc. But they are also found, sometimes in large quantities, at 

 the roots of living plants, and ultimately cause the death of these 

 plants. Hewitt (18) found that an Enchytraeid, viz. Fride7ncia 

 hisetosa Levinsen, was the direct cause of the death of a number 

 of larch seedlings. It became a great pest in the nursery, killing 

 off the seedlings by eating away the living cortical tissue of the 

 main root. 



I, also, have found Enchytraeids at the roots of living plants. 

 In this case, the plant attacked was Antirrhinum from a garden 

 in Edgbaston, Birmingham. The particular Enchytrseid causing 

 the da,mage was Enchytrceus argenteus Mich, As in the case of 

 the larch seedlings, the Enchytraeids were found at the roots, 

 destroying the living cortical tissue and leaving the central woody 

 cylinder exposed. 



On account of this the Enchytraeids are probably of great 

 interest from an agricultural point of view, and this paper- is a 

 preliminary attempt to discover the economic significance of these 

 "white worms." 



The Enchytraeid I have chosen for this paper is Enchyti-mus 

 pellucidus Friend (6), chiefly because I have an abundant supply of 

 these worms, but also because I think this species is a good type 

 of the whole genus Enchytrceus, 



There is a difficulty in determining some species of the 

 Enchytrasidae, since the specific differences are sometimes very 

 small. After having closely examined many specimens of 

 Enchytrceus pellucidus and also specimens of Enchytrceus cdbidus 

 Henle, which I was able to obtain in large quantities, I have come 

 to the conclusion that E. pellucidtis cannot be regarded as a 

 distinct species, but only as a variety of E. cdbidus, and differing 

 only slightly from it. According to Michaelsen (10), thirteeji 

 authors have, in eighteen papers, given to this y^orm, Enchytrceus 

 cdbidus, five generic and twelve specific names, so that it is 

 evidently fairly comnion and probably varies in different 

 localities. 



Two of the chief distinctions between E. albidus and 



