part of Mareli to the latter part of June), of the entire nightly col- 

 lections made by the beetle pickers in cane fields, showed that less 

 than one per cent of the ^lay-beetles collected from sugar-cane foliage 

 belonged to this species, the remainder being adults of the common 

 sugar-cane white-grub (P. vandinei). 



The following table, which is reprinted (revised) from the Third 

 Report of the Board of Commissioners of Agriculture (page 43), 

 gives the actual numbers of beetles of the two species collected on 

 the various nights: 



The period of activity of adults of this species is much shorter 

 in duration than that of P. candinei. Appearing at about the same 

 time of the spring, during the latter part of February, it reaches a 

 maximum abundance about middle April to early May, then begins 

 to decrease in numbers and entirely disappears from the fields by 

 the middle of July. In fact, usually only a few are to be found after 

 the middle of June. Having a life-cycle of one year, like P. van- 

 dinei, it is hard to account for the fact that this species confines its 

 appearance in the adult stage to a short season of the year. 



Collections of adults recently made by the writer at Yauco and 

 Santa Rita on May 3 and 4 have shown that tliis species, outside 

 of cane fields, is equally abundant to P. vandinei in tlie Guanica dis- 

 trict in the spring of the year. It was noticeable, however, that the 

 beetles fed largely upon trees and plants not frequented by the larger 

 species. They were particularly abundant on the foliage of Lantan^ 

 camara, the black sage {('ordia cijlindrostachya), and the near tree 

 (Bncida huceras), all of which grow in the upland, along fences or 

 scattered through pasture land, and none of which are extensively 

 fed upon by P. Vandinei. This leads to the belief that the grub of 

 this species is a sod-fre(iuenting one, preferring dry upland soils, 

 and has not yet taken to the cane fields to any extent. 



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