14 EXPERIMENT STATION. [Jan. 



17. Color vision in Ix^es. 



A number of these lines of investigation are .well advanced, 

 tliongh none can be regarded as brought to completion. Suffi- 

 cient progress has, however, been made in connection with a 

 number of them to warrant publication, and technical papers 

 covering some phases of this work will be found in later pages. 

 The more important are as follows : — 



The natural fertility of cranlx'rry bogs. 



Tobacco injury due to malnutrition or overfertilization. 



Variation, correlation and heredity in garden peas. 



The eflect of fertilizer on variation in corn and beans. 



The chemistry of arsenical insecticides. 



'"'Cranberey Substation. 



Dr. II. J. Franklin remains in local charge of the business 

 and investigational work connected with our cranberry sub- 

 station, lie has devoted himself to the matters in his charge 

 with the greatest faithfulness and cntliusiasm, and it is a pleas- 

 ure to testify to the great value of his services. 



During the past year our equi])ment for work in the interests 

 of cranberry growers at the substation in East Wareham has 

 been much increased and a large amount of construction work 

 has been done. The princi])al im])rovement made has been the 

 erection of a building. This building contains a large screening 

 and packing room, living and office rooms for the local officer in 

 charge, a small laboratory, and large basement and cellar stor- 

 age rooms.. The cost of the building was about $2,000. 



Dr. Franklin furnishes the following description of special 

 construction at the station bog completed during the year: — 



1. Flooding Areas. — Five separate areas were diked off on 

 the station bog for experiments in flooding. Four of the areas 

 contain a])Out one-fifteenth of an acre each and the fifth con- 

 tains about an eiglith of an acre. These areas are all separated 

 from each other by dikes and narrow check strips. The dikes 

 were built of turf and sand in the usual way, and average about 

 20 inches in height and 3 feet in width. In all, about 1,100 

 running feet of this diking was built. A canal, al)r)ut 450 feet 

 long and 3 feet wide, was constructed around the margin of the 



