June 30. — Two more lesions of 2 mm. on other side. 

 Aug. 5.— Dead and black, including head. 



(8) May 26. — Tip of one leg with bacterial lesion. 

 July 7. — Half of same leg off from disease. 

 Aug. 21. — Grub dead and discolored. 



(9) June 28. — Grub pupating; left middle leg eaten off. 

 July 2. — Pupa has a left leg, but small. 



July 20. — Adult issued, imperfect; died. 

 (10) June 27. — Grub has lesion on head; two back legs infected (2d instar). 

 July 5. — Has molted to third instar; two back legs smaller. 

 Dec. 11. — Grub dead; discolored. 



This bacterial disease can hardly be considered as possessing any 

 great possibilities as a means of artificial control of white-grubs, for 

 as seen by the observations cited above, its action in producing deatli 

 of the grub is slow, requiring in some cases months, under conditions 

 that may be considered ideal for its development. Whether it ever 

 produces fatality of grubs on a large scale in the fields in Porto Rico, 

 at such times as during periods of heavy rainfall, as it is credited 

 with doing in some sections of the United States, is a question open 

 to further investigation. 



THE COMMON WHITE-GRUB. 

 Phyllophaga portoricensis n. sp.* 



This species is the eastern analogue of P. vandinei occurring at 

 tlie western end of the Island. Its distribution covers approximately 

 the eastern two-thirds of the Island, being defined in the west by 

 a line running more or less north and south through the towns of 

 Vega Baja on the north coast and Ponce on the south. So far as at 

 present known, its eastern limit on the Island is defined by the east 

 coast. Specimens that have been recently collected on the Island of 

 Vieques, adjoining Porto Rico to the east, appear to ])elong to this 

 species, so far as genital characters show, though being somewhat 

 larger and lighter in color. 



In spite of its wider distribution, tliis species has not gained as a 

 pest the prominence of the preceding. Damage by it, while most 

 accentuated in the sugar plantations, is by no means confined to them. 

 Its grub is particularly injurious in coffee groves and pineapple plan- 

 tations. As pines are usually not plowed up until some time after 

 the main crop is harvested, damage from white-grubs may often 

 go unnoticed, or be attributed to poor soil. AVe have received fre- 



* This species has been mentioned, as a supposed variety of P. vandinei, under (he 

 name of "Laclinosterna (/raiHle (northern form)," in the Fourtli Report of the Board of 

 Commissioners of Agriculture of Porto Rico, page 48. 



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