-642- 
INSECT CONDITIONS IN PORTO RICO DURING- SEPTEMBER, 1931 
M. D. Leonard 
Insular Experiment Station, Rio Piedras, Porto Rico 
The sugarcane "borer ( Diatraea sac char al is Fa"b.) was worse, according 
to S. C. McCall, local Manager of the United Porto Rican Sugar Company on 
Vieques Island, on the 1931 crop, a total of about 3,500 acres, than it was 
during the two previous years. He stated that Japanese cane, usually sup- 
posed to be somewhat less infested than other varieties, was the worst in- 
fested of all during this past year. 
Adults of Dyscinetus "barbatus Fab. "began appearing again at lights on 
September 2 at Isabela (G.N.W.). 
The yellow sugarcane aphid ( Sinha flava Forbes) was reported on Septem- 
ber 27 by S. C. McCall to have been absent on Vieques Island during -the -cast 
year as far as he could observe. Its absence or at least scarcity was 
probably due to much more than normal rainfall on that Island. 
The leafhopper, Protalebra brasiliensis De Long , known to be a minor 
pest of sugarcane, has continued abundant throughout the month on Bidens pi- 
l o'sa at 31 Horro in San Juan. 
The coffee stem borer ( Psychono c tua personali s Grote) was received 
under date of September 29 in injured branches of coffee trees from Corozal 
with the statement that considerable damage was being done to the trees by 
the hollowed-out branches being broken off when they were bent down by the 
pickers. 
The coffee leaf miner ( Leucoptera coffeella Staint.) was generally 
distributed and quite abundant on a large coffee farm in the vicinity of 
Jayuya, visited September 9-10. Apparently not much damage was being done, 
however, to bearing trees. 
The green scale ( Coccus viridis Green) was observed September 9-10, 
to be general, though not very abundant on a large coffee farm near Jayuya, 
the younger leaves and shoots being more commonly infested as usual. 
The coconut scale ( As-pi dipt us destructor Sign.) was reported by Mendez, 
Coconut Specialist at the Insular Station, as being not nearly so abundant 
at Cabo Rojo during September as it was five or six months ago. As far as 
could be observed, on September 26 practically every coconut palm on Vieques 
Island was more or less infested with the coconut scale, those towards the 
eastern and drier end of the Island especially so, many palms having a 
sickly and yellow appearance and in some cases even the fruits being almost 
encrus.t ed- wi £h«, £he seal e s . 
