COPUr.ATION AND OviPOSITIOX. 



Copulation takes place immediately upon the cessation of fliglit. 

 and before feeding begins, normally between 7 :30 and 8 :15 F. M. 

 In rearing cages it takes place a little earlier, because the Higlit 

 lasts a shorter length of time than under outdoor conditions. Copu- 

 lation lasts about thirty minutes. 



In the same cage in which the observations on flight were made, 

 the following notes were recorded on an evening of September 2 : 

 Quite a number of females were seen at about 8 :40 P. ^l., resting 

 both on the screening and on foliage with the genitalia protruded, in 

 receptive condition. The scarcity of males in the cage accounted 

 for the fact that no copulation was seen. Beetles remain quiet in 

 this position for some minutes before they begin feeding. 



Experiments to determine the rate of egg laying of this species 

 are in progress, but have not been completed. The beetle's life 

 above ground is believed to last normally between two and three 

 months, and the egg-laying period to cover in the neighborhood of 

 a month. 



Insect Parasitism. 



The insect parasites of this May-beetle are identical with those 

 of P. vandinei, the Tachinid parasite Crypfomeigenia aunfacies; AYal- 

 ton being the most useful parasite of adults, and the predacious wire- 

 worm. Pjfrophorus luminosus llliger. the most efficient insect enemy 

 of the grubs. These two parasites are very doubtless responsible, 

 in large measure, for the fact that this May-beetle has not cr*rsed 

 the disastrous and widespread damage to sugar-cane properties on 

 the north and east coasts that P. vandinei has caused in the Guanica 

 district, where neither of the two parasites occur. 



Thifortunately, all of our notes relating to the Tachinid parasite 

 Entri.roides jonesii Walton, which were made previous to 1916, fail 

 to indicate wOiat species of Phyllophaga were the hosts, since at that 

 time the different species were not distinguished. Necessarily, in 

 the Aiiasco district the host was one of the two species P. vandinei or 

 P. citri, or perhaps both, and in the San Juan district must have been 

 either P. citri or tlie present species, if not both. Further observa- 

 tions will be necessary to determine the exact host of this fly. 



A Scoliid wasp known as Elis xanthonotus Rohwer, the female of 

 which is black with a red spot on the thorox and the male black with 

 yellow cross bands, found very commonly in the fall in the vicinity 

 of Rio Piedras, may prove to be a parasite of this species or of P. citri, 

 01" both. Observations have not thus far revealed the host of the 

 wasp. 



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