82 JOURNAL OF THE 



tory of the nematode, though some of the economic suggestions 

 possess value. It is but just to Dr. Riley to say that he is not 

 personally responsible for the en-ors contained in the Bulletin, 

 since he states in an introductory paragraph {loc. cit.) that the 

 nematodes "do not, in a zoological sense, strictly belong to the 

 Division work. * ^ * 'pj^e Bulletin niakes no pretense to 

 be a scientific treatise on the life history of these worms, but is 

 in the main an effort to ascertain a suitable remedy. The gen- 

 eral literature on the subject has not been at Dr. Ncal's (.'om- 

 mand, and my time is so fully occupied otherwise that I can do 

 little or nothing at present in the way of identification of species 

 or of comparing Dr. XeaPs results with those of European 

 investigators, which, as a n)atter of fact, are of little practical 

 importance.^' 



The conditions this autumn at Auburn have been quite favor- 

 able for determining a number of interesting facts relating to 

 the development and transformations of this nematode, as well 

 as the duration of a life cycle showing the number of successive 

 generations in a vear. 



IL 



EXTERNAL CHARACTERS OF THE DISEASE. 



By a reference to Plates I, II and III the external characters 

 of the disease can be seen. These plates represent respectively 

 '^knotted" specimens of the roots of the Irish potato, tomato 

 and parsnip and salsify. Plates I and III are natural size; 

 Plate II is reduced to two-thirds natural size. All are from 

 average specimens. The abnormal growths on the tomato root 

 appear as irregularly fusiform, knotty or nodulate enlargements, 

 two to ten times the natural diameter of the roots. The surface 

 of the gall is at first smooth, more or less undulate or papillate, 

 but becomes later roughened, scurfy or cracked, and finally decay 

 of the tissues sets in. The tap root and the earlier lateral roots 

 were attacked early in the season, and when the photograph was 

 taken they were partially decayed and falling to pieces. When 

 the roots begin to die they send out new roots in the efforts of 



