Island, all native, which makes an unusually good representation as 

 compared with other islands of the West Indies. These fall into 

 three groups, six of them being Hymenopterous (all Scoliid). two 

 of them Dipterous (both Tachinid), and one Coleopterous (Elaterid), 

 Those of the first and last groups attack only the grubs, while the 

 Diptera attack only the adults. 



We may add to these four others, all of which liave been observed 

 attacking the grubs (or eggs) under laboratory conditions only. One 

 of them is a white nematode, not exceeding 5 or 6 mm. in lengtli, 

 which on several occasions gave trouble l)y destroying the eggs in 

 experimental jars. More troublesome than the nematodes was a spe- 

 cies of minute, glo])ular white mite (Tyroghjpkus sp. ?), which at- 

 tacked all stages of the beetles, from egg to adult, and was the cause 

 of a high per cent of mortality in experimental jars and boxes. 



Of minor importance were a Staphylinid beetle larva (species 

 undetermined) and a wireworm, the young of an p]laterid I)eptle 

 (Monocrepidius sp.), both of which were observed to feed upon j\Iay- 

 beetle eggs in experimental jars. Both were introduced with eartJi 

 enriched with manure, and it is not l)elieved they would ever cause 

 mortality of eggs under natural conditions in the field. 



The following list will serve as a guide to the known white-grub 

 parasites of the Island. The more important of them will be dis- 

 cussed later under the species they attack. 



' The deteiminations of the wasps (except Seatia atiata Pab.. which was deterrriiried by 

 tlie Am. Mils. \at. Hist.) in this list were made by S. .\. Roliwcr, of the flies by W. R. 

 Walton, and of the beetle by E. A. Scliwaiz. 



I'he only one of these parasites wiiii-h lias Ix-en found hyperi)iii'a- 

 sitized is ('ampsomcris dorsata Feb.. a dead adult of which was found 

 at Santa Kita containing a single i)i|)t('rous pupariiiiii. about •"> inin. 

 long, from which issued, on -luiic IS. I!)!:!, ten small Cluilcidids, 

 wliicli have not been determined. 



55 



