216 



SLUGS, FLUKES, EELWORMS, ETC. 



excessive slenderness that cannot be conveyed by com- 

 monly intelligible terms of measurement. Males, 

 females, young wormlets, and eggs, may be found 

 together in the infested shoots. 



These Eelworms belong to the family of the 

 Anguillulidce, of the order Nematoda, or " Thread- 

 worms"; and of these Anguillididce, there are many 

 genera or divisions, as they may be called. These are 

 •distinguishable from each other in part by the form 



Fig. L59.—" Tulip-rooted " Oat-plant. 



of the (esophagus or gullet, and also by the presence, 

 or absence, of a point, known as a "spear," in the 

 opening of the mouth cavity. The figure (preceding 

 page) shows some of these distinctions ; it will be ob- 

 served that at 1 there is a spear with a large base ; at 

 2, a spear without a large base ; and at 3, there is no 

 obvious spear. These distinctions, however, and the 

 others which are figured, are totally invisible without 

 a powerful magnifier. It will be noticed that the 

 figure only gives a portion of the head and tail ends ; 

 if the whole was represented, the wormlet would have 

 to be shown (at its present magnified width) as from 

 at least eight or nine inches to a foot long. 



Keturning now to the infestation of Stem Eelworm. 

 In the case of Tulip-rooted Oats, there arc usually, as 



