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the natural conditions which prevail in the field. We have included in 

 every package of infection sent out from the laboratory at least six or 

 eight dead bugs with the full external growth of the Sporotrichum. 

 The attacked area in tlie State of Kansas has moved nortliward i'rom 

 the area most destructively infested last year. The southern counties 

 of the State, where the bugs were quite destructive in 1893, and where 

 large quantities of Sporotrichum were sent from our laboratory, seem 

 to be comparatively free from chinch bugs in 1894. Our station is located 

 in about the center of the eastern fourth of the State, and for the first 

 time since the beginning of our experiments the chinch bugs have 

 attacked fields in the immediate vicinity of our laboratory. This gave 

 us the first opportunity of conducting an experiment which could be 

 under our own personal daily supervision from beginning to end. Inas- 

 much as this may be taken as a standard example of the manner in 

 which the Sporotrichum works in the field, I will append the following 

 notes : 



Fig. 18. — Diagram of field infested with chinch bug (from sketch by F. H. Snow). 



The field experimented upon was a corn field 100 rods in length, a 

 portion of which joined the University campus, and the remainder a 

 wheat field from which the wheat was cut on June 20. The above 

 diagram will give the relative position of the fields and will illustrate 

 the accompanying explanation : 



When the wheat was cut it was noticed for the first time that chiuch 

 bugs were abundant in the wheat. They moved immediately from the 

 wheat field into the adjacent corn field belonging to another owner. 

 The bugs were first noticed by him in the corn in large force, in both 

 A and B, blackening the stalks, on Saturday, June 23. The bugs were 

 in about 20 rows in A and about 10 rows in B. The strip of potatoes 

 between corn in B and wheat field had hindered the bugs in their prog- 

 ress into B. The contents of one of the laboratory boxes of the 24 by 

 30 by <) inches dimensions was taken out, earth and all, and used for 



