February 14, 1913] 



SCIENCE 



259 



U 



Fig. 5(6). The number of pupils, reporting 

 themselves as expecting not to complete the cx)urse, 

 who leave in each successive year. 



Fig. 6. The median expectation of length of 

 stay in high school for pupils according to the 

 family's monthly expense for rental. 



Fig. 7. The median expectation of length of 

 stay in high school of pupils who during the first 

 term were rated by their teachers as shown at the 

 left of the diagram. 



Left in first year 



Left in second year 



Left in third year 



Left in fourth year 



Graduated 



Fig. 8(a). The number of pupOs, ranked in the 

 top tenth for ability, who leave in each successive 

 year. 



Left in first year 

 Left in second year 



Left in third year 



Left in fourth year 



In school in fifth year 

 Graduated 



P 



Fig. 8(6). The number of pupils, ranked in the 

 bottom tenth for ability, who leave in each suc- 

 cessive year. 



SPECIAL ARTICLES 



A WILD HOST-PLANT OF THE BOLL-WEEVIL 

 m ARIZONA 



As cultivated cotton is the only plant thus 

 far known to harbor the boll-weevil, the exist- 

 ence of another host-plant of these destructive 

 insects may be worthy of notice. The plant 



