lgQ(S.S.482) THE MONONCHS 



such organism is reared in the midst of a host of other organisms, visible 

 and invisible, and often it is these others that determine agricultural suc- 

 cess or failure. 



The soil is the habitation of a vast community of beings with all the 

 attributes of other huge agglomerations of living things having varying 

 needs, instincts and aspirations; and it is just as inappropriate to look 

 upon it as inorganic as it would be to look upon a great city as merely an 

 agglomeration of hills, streets and houses. Here in the soil are beings in 

 enormous variety; multiplying, growing, dying; competing, fighting, co- 

 operating one with another, with an activity almost if not quite defying 

 the imagination, and we need what may be called soil biologists or geo- 

 biologists, who shall understand, as far as possible, this interplay of life 

 forces that gives us food, fiber and fuel. To a considerable degree our 

 progress in agricultural knowledge in the not distant future will be in pro- 

 portion to the firmness with which we lay hold of and act on this idea. 



SUMMARY 



1. The genus Mononchus is composed of scores, possibly hundreds, 

 of species, divisible into distinct subgenera. The number of known 

 species is hereby more than doubled. 



2. The genus is of world-wide distribution, and many of the species 

 are cosmopolitan. Mononchs occur in all kinds of arable soil, sometimes 

 in hundreds of millions per acre. 



3. Most mononchs, probably all, are strictly carnivorous. They feed 

 on a variety of living microzoa, prominent among which are other nemas. 



4. Injurious nemas are devoured by mononchs, and it is desirable that 

 this trait of mononchs be carefully investigated with a view to utilizing it, 

 if possible, in diminishing the enormous crop losses due to plant infesting 

 nemas losses amounting to many millions of dollars annually. 



5. The lips are moved by long muscles, connecting proximally with 

 the body wall behind the pharynx. These muscles lie along the outer 

 surface of the pharyngeal capsule and act in such a way as to pull the 

 lips inward and outward radially about a series of fulcra existing in a 

 framework encircling the head along the margin of the pharynx. The 

 lips are the mechanical complements of the dorsal tooth and denticles. 

 While most mononchs bolt their food, some give it a certain degree of 

 mastication. The appetite is sometimes voracious. 



6. Many mononchs, probably most, are hermaphroditic, even to the 

 degree of syngonism. In the typical case investigated the minute sperm 

 cells of female origin are functional. 



7. Well developed glands, salivary in character, occur in the mon- 

 onch oesophagus, and empty duectly into its lumen, and both indirectly 

 and directly into the mouth cavity. 



