132 Recent Literature. |_Auk 



of leafhoppers, apply just as well to their other enemies. For instance 

 he says (p. 32) of the genus Reduriolus of the Heteroptera, I "believe them 

 to be one of the principal agencies in keeping the leafhoppers in check." 

 Why does he not say the Heteroptera are of no importance as enemies of 

 leafhoppers because only a small proportion of the species have been 

 observed to attack them? This argument would be by no means so far 

 fetched as that relating to birds on p. 23, namely, that as leafhoppers were 

 found in only 170 stomachs out of 47,000 examined, birds " very properly 

 may be considered as negligible in any consideration of the natural agencies 

 of control." 



Osborn's further remarks that "it is useless to depend on birds for con- 

 trol of these insects. No amount of ' encouragement for the birds ' or efforts 

 to utilize their service in this direction can be expected to have any appreci- 

 able effect in reducing the number of leafhoppers, and we may dismiss this 

 idea and turn our attention to other more hopeful agencies," are futile and 

 gratuitous. This relation of enemies to prey is true not only of birds but 

 of all natural enemies under natural conditions. It has been possible only 

 in a very few cases to use any kind of natural enemies with striking success 

 and as for control, it has never been accomplished except for limited areas 

 by methods such as are now used in the distribution of the ladybird Hippo- 

 da»iia convergent by the California Board of Horticulture. 



Some find it difficult to accept the inevitable truths regarding natural 

 enemies, but happily extravagant claims for this enemy or condemnation 

 of that, are largely disappearing from modern publications. All natural 

 enemies should be given credit for useful tendencies, and their protection 

 urged, but the fact must never be obscured that to obtain the degree of 

 control necessary to commercial success, man must practically invariably 

 depend upon direct suppressive measures of his own devising. — W. L. M. 



Economic Ornithology in California. — Mr. Harold C. Bryant, who is 

 working as a fellow in applied zoology on the State Fish and Game Com- 

 mission foundation in the University of California, is devoting his attention 

 to problems in economic ornithology. With Professor F. E. L. Beal's com- 

 prehensive work, embodied in Biological Survey Bulletins 30 and 34, as a 

 general treatment of the subject and with intelligently directed local work 

 such as Mr. Bryant is doing, to fill in the details, the economic ornithology 

 of California will be better understood than that of any other state. Mr. 

 Bryant has already published several papers dealing with his investigations, 

 three of which are here reviewed. 



1 The economic status of the Meadowlark in California, has for some 

 years been a burning question and naturally this problem has occupied 

 much of Mr. Bryant's time. He has recently published a preliminary 

 paper on the subject. 1 Ranchers in the San Joaquin and Sacramento 

 Valleys report the loss of from one-third to one-half of their grain crops 



" Monthly Bull. State Comm. Bort. 1. No. 0, May, 1912, pp. _ > _ > 6-23l. 



