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[Vol. S 



upon beans would reduce their numbers considerably. Black-eyed 

 peas, which are commonly grown in gardens in the south, should also 

 be included, and wild host plants should be destroyed. 



The date of planting a crop of cowpeas is also an important consid- 

 eration. It has become a well established custom not to plant cow- 

 peas until June. This custom has come about apparently from the 

 ravages caused by this beetle on an early crop. It is important to 

 dodge the first generation of beetles in order to allow the plants to 

 make a good growth before the second generation appears and to 

 allow the poisoning of the adults on beans to take place. This can 

 probably be done in the latitude under consideration if peas are not 

 sown earlier than the latter part of May. 



There seemed to be a possibility of finding a resistant variety of 

 eowpeas, and accordingly experiments were started to determine this 

 point, the Bureau of Plant Industry furnishing the seed. This phase 

 of the work is still being carried on, but it may be said that no variety 

 is entirely immune. The Iron cowpea is damaged much less, both 

 by larv2e and adults, than any variety so far experimented with. 

 In view of the fact that it is also resistant to the root-knot disease, 

 it promises well for the purpose of soil renovation wherever it is 

 adapted to soil and climate. 



References 



^ PoPENOE, E. A. Transactions Kansas Academy of Science, 1877, p. 35. 

 2 Webster, F. M. Report, Commissioner of Agriculture, 1887, p. 152. 

 2 PoPENOE, E. A. Second Report Experiment Station of Kansas, 1899, pp. 210-12. 

 ^ Chittenden, F. H. Proceedings Entomological Society of Washington, Vol. II, 

 1892, pp. 263-4. 



^ Chittenden, F. H. Division of Entomology, Bull. 9, n. s., 1897, pp. 64-71. 

 « Weed, H. E. Insect Life, Vol. V, 1893, pp. 110-111. 



Mr. F. M. Webster: I only wish to point out the far-reaching 

 results of these investigations. Following the idea put forward by 

 Dr. Forbes last night, I think this furnishes an excellent illustration. 

 We began twenty-eight years ago with the investigation of a beetle 

 whose injuries were supposed to be restricted to the foliage of legu- 

 minous plants. Now we find ourselves at a point where we have to 

 go to the ecologist, and the soil expert, as we find that the larvae 

 of this beetle in destroying these nitrogenous nodules, largely takes 

 away the fertilizing value of these plants, especially if growing on the 

 higher lands where there is the greatest need of additional fertility. 

 And it takes us into a matter which the agronomist has overlooked. 



