description and seasonal history. 15 



Investigations of Vertebrate Enemies. 



In order to determine what assistance might be expected from birds 

 and other animals besides insects, arrangements were made with the 

 Biological Survey to send an assistant to Salt Lake in order to carry 

 out extended investigations along this line. Mr. E. R. Kalmbach 

 was detailed for this work by the Chief of the Biological Survey and 

 proceeded to Salt Lake, Utah, making continuous observations there 

 from May 7 to July 5, 1911. 



It is not possible at the present time to give the results of this work 

 in detail, but a list of the vertebrate enemies observed attacking the 

 alfalfa weevil will be found under the heading Natural Enemies. 



THE INSECT NOT CORRECTLY DETERMINED. 



In the bulletin of the Utah Experiment Station, to which reference 

 has already been made, the name of the insect is given as Phytonomus 

 murinus Fab., and this name was also applied to the same insect by 

 the writer in Circular No. 137 of the Bureau of Entomology, issued 

 April 20, 1911. It had been so determined by one of the best 

 American authorities on this order of insects. It has, however, 

 proved to be a closely related insect (Phytonomus posticus Gyll.), 

 much more common and injurious to alfalfa in Europe, western 

 Asia, and northern Africa, and in these countries known generally as 

 P. variabilis Hbst., meaning literally the variable Phytonomus. It 

 is, however, less destructive in the Eastern Hemisphere than it bids 

 fair to be in this country, because of its natural enemies at home, 

 which, as it appears, were not brought over with it when it was first 

 introduced. 



APPEARANCE OF A SECOND SPECIES IN UTAH. 



A much larger species, Hypera punctata Fab. (fig. 2), the clover- 

 leaf weevil, has recently been found about Malad, Idaho, by Mr. 

 H. T. Osborn, and about Ogden, Utah, by Mr. E. J. Vosler, both 

 of this bureau. This is a larger insect than the alfalfa weevil, but 

 may be confused with it by the ordinary farmer. It had not before 

 been observed between the Rocky Mountains and the Cascades. 



While known as a clover insect, this last beetle did some damage 

 to alfalfa in Virginia during June, 1910. 



DESCRIPTION AND SEASONAL HISTORY OF THE ALFALFA WEEVIL. 



The fully-developed alfalfa weevil, Phytonomus posticus Gyll. (fig. 1), 

 is a small, rather insignificant appearing beetle, slightly under one- 

 fourth of an inch long, of a brown color, mixed with gray and black 

 hairs arranged in indistinct spots and stripes on the back, as shown 

 in figure 1 . Rubbed individuals may be very dark, verging on black. 



