Outside of Porto Kico. El it; snciiu:ta Fah. (?) was collected by 

 the writer in great abundance on IMona Island in December. 1913, 

 where it occurred on the leaves of corn infested with Peregrinns 

 mairlis. Campsomcris pijrura Roh. was taken commonly at Higueral, 

 Santo Domingo, in February. 1914. and a few also were taken on 

 jNFona Island. 



EFFICIENCY OF WHITE-GRUB PARASITES IX i'ORTO RICO. 



Our knowledge of the white-grub parasites of the Island is at 

 present very limited, and much is yet to be done in the working out 

 of hosts and life-histories of the various species. 



Of the nine species of Avhite-grub parasites listed above, there is 

 direct evidence of only one of them destroying the grubs of I'hyUo- 

 phaga. This is the Elaterid beetle. Pyroplwrus InminosHs 111., larvae 

 of which have been fed upon PhyJlophaga grubs for long periods in 

 coufineraent in the insectary. Field observations of this wireworm 

 preying upon white-grubs are still too few to make any definite state- 

 ment as to its value in white-grub control. The beetle is extremely 

 abundant in the spring and summer on the north and west sides of 

 the Island ; if true that it destroys white-grubs under outdoor con- 

 ditions, its presence may perhaps account in part for the lesser injury 

 from grubs in the sections where it abounds. 



Some of our earlier notes (for the year 1911) credit Campsomcris 

 dorsata Fab. with being a parasite of Phyllophaga grubs (30, p. 36). 

 But in all cases the grub determinations were doubtful. It seems 

 probable that the parasitized grubs in question, if not of DgscineUis, 

 which closely resembles Pln/JJophaga in the larval stage, were of 

 Ligijfus tumulosus Burm., whose grub is abundantly parasitized at 

 all seasons by Campsomcris. 



It may develop, with additional observation, that the two species 

 of Elis occurring here one or l)oth parasitize grubs of Phijllapliaga 

 in restricted localities. Yet the strange fact remains that of tiiou- 

 sands of PJiylluphaga grubs collected in cane fields, and examined 

 by the writer, not one has ever been found parasitized ])y a Scoliid 

 egg or larva. 



THE TACHINID PARASITES. 



Our present knowledge of white-grub conditions leads to a l)elief 

 that the most imi)ortant and active agency in the control of white- 

 grubs in Porto Rico is the work of the two Tachinid flies, Cit/pfo- 

 meigenia aurifacies Wal. (PI. VII, fig. 7) and tJidri.roidcs jonem 

 VVal., upon the adults. Like the Piirophorus I)eetle, these flies seem 



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