1907.] White-grubs and May-beetles. 465 



Our data show about thirty cases of oviposition by seven of our 

 species in our"bree"ding-cages, ranging in date from the ist of June 

 to the middle of July.* As the beetles have begun to emerge more 

 than two months earlier, it is likely that they spend some time in 

 feeding before oviposition begins. In the Eighteenth Report of 

 this office it is said (p. ii8) that the statement commonly made to 

 the effect that the eggs are laid in a ball of earth is clearly errone- 

 ous. This assertion must be corrected in the light of numerous ex- 

 periments made in my insectary in 1906 with May-beetles of several, 

 species, all of which so deposited their eggs in the ground that each 

 was found inclosed within an earthen ball, a half inch in diameter, 

 probably formed by the extrusion with the egg of an adhesive fluid 

 which, upon hardening, held together the particles of earth which it 

 had penetrated. This method of inclosure was so general that eggs 

 were most easily found by sifting the dirt in breeding-cages and 

 breaking open the spherical pellets of earth thus separated. The 

 eggs were laid at depths varying from not more than an inch to 

 five or six inches below the surface, the number for each female 

 varying from 44 for a specimen of L. inversa to 67 for L. implicita. 

 The following extract from the breeding-cage report of Mr. J. 

 J. Davis will give additional particulars of interest. 



L. inversa. June 12, 1906, i female beetle in breeding-cage. 

 June 18, the earth examined and 44. eggs found, each in a ball of 

 earth from 3 to 3>1 inches below the surface. Eggs of a pure milky 

 color and of an oval shape, measuring i J4 X 2 mm. By the end of 

 three days they had swollen to a nearly spherical form, now measur- 

 ing 2 X 2>4 inm- Hatching first observed July 11. 



t,. hirticula. Beetles collected and placed in breeding-cage June 

 19, 1906. No eggs were found till July 2, but July 9, 6 were found, 

 each in its ball of earth. The freshest eggs were white with a 

 glossy luster. They measured at first from i>^ X 2 mm. to 2 X 23^ 

 mm. Five days later these eggs had swollen to 2 mm. in diameter, 

 and were 2j^ to 2^ mm. in length. 



L. ephelida. A single egg obtained August 4, 1905, from beetles 

 collected at Carbondale, 111., July 26, and placed in breeding-cage 

 in insectary July 29. This egg was comparatively small and defi- 

 nitely oval, measuring at first i>^ X 2 mm., and later 1^X2 mm. 

 L. ilicis. From beetles collected June 19, 1906, eggs were found 

 in oval balls of earth July 9, none having been present there on the 

 2d of that month. The eggs were a dull white, quite different from 

 the glossy luster of those of L. hirticula. They measured at first 



*A specimen of L. ephelida, taken July 2<), WOS, at Carbondale, in sontliern Illinois, laid 

 eggs until Ang-nst 4. 



