4 BULLETIN 1243, U. S. DEPARTMENT OF AGRICULTURE. 



The Mexican bean beetle belongs to the family Coccinelliche, or lady- 

 birds, and all the known species in this country are beneficial except 

 the insect under discussion and the squash lady-beetle (Epilachna 

 borealis Fab.). The Mexican bean beetle has never been known to 

 eat other insects, and it resembles more closely in many ways the 

 family of leaf-eating beetles, or Chrysomelidse, than the Coccinellidse. 



DISTRIBUTION. 3 



The rapid spread of the Mexican bean beetle since its introduction 

 into the Southeast has been remarkable. In 1920, late in the sum- 

 mer, Dr. W. E. Hinds and coworkers found 13 counties infested in 



northern Alabama. In 1921 a 

 rapid spread in all directions 

 took place, especially to the 

 northeast. By fall the insect 

 was found in portions of six 

 States, over an area of approxi- 

 mately 40,000 square miles, as 

 compared with 4,500 square 

 miles infested the previous year. 

 The distribution in 1922 in the 

 Southeast, so far as known, 

 covered at least 70,000 square 

 miles in seven States. (See 

 map, fig. 5.) 



An isolated infestation was 

 reported in 1921 at Thomas- 

 ville, Ga., near the Florida line. 

 This infestation covered 14 

 square miles. No appreciable 

 spread in this locality occurred 

 during 1922, only 3 additional square miles being infested. 



The spread in general has been decidedly to the north. In the 

 fall of 1920 the most northern locality found to be infested was 

 Dekalb County, Ala. One year later the infestation had reached 

 Whitley and McCreary Counties, Ky., Hawkins County, Tenn., and 

 Greenville County, S. C, all of which points are more than 200 miles 

 from Dekalb County, Ala. In 1922 this rapid spread continued, and 

 the insect traversed an area 110 miles across to the northwest at its 

 widest point, viz, from Whitley and McCreary Counties to Bullitt 

 County, Ky. No records are available and no scouting was done in 

 eastern Kentucky. It is certain, however, that the insect is present 

 at least over the territory southeast of Madison, Jackson and Clay 

 Counties. Fayette County, Ky., and Lee and Scott Counties, Va., 

 were scouted by the Bureau of 'Entomology and found to be infested. 



3 Since this paper was prepared new records of spread have been received, chiefly through the coopera- 

 tion of entomologists in the States concerned. The beetle is now present in the following localities in 

 addition to those mentioned above: Ross, Gallia, Jackson, Adams, Highland, Pike, Scioto, and Frank- 

 lin Counties, Ohio; Ashe, Avery , Burke, Cleveland, Gaston, Lincoln, McDowell, Polk, Rutherford. Watauga, 

 Buncombe, Madison, and Yancey Counties, N. C; Abbeville, Cherokee, and Spartanburg Counties, 

 S. C; Lamar County, Ga.; Washington and Unicoi Counties, Tenn.; Lee County, Ala.; Tishomingo and 

 Itawamba Counties," Miss.; Spencer, Meade, Letcher, Laurel, Bell, Clay, Estill, Harlan, Leslie, Ousley, 

 and Perry Counties, Ky.; and Russell and Wise Counties, Va. 



Fig. 4. — Young larvae of the Mexican bean beetle cling 

 ing to eggshells a short time after hatching. 



