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adults after emerging concentrate on the remaining plants and deposit eggs 
in the area immediately surrounding the plants. Later in the season the 
newly emerged and older larvae attack the developing nuts, chewing away 
portions of the hulls, and often boring through the hull and destroying 
the kernel. The nuts of the chufa are injured in the same manner as are 
those of peanuts. 
Irish potatoes are very susceptible to larval injury and serious 
damage has been observed to this crop at Florala, Ala., and Gulfport and 
Laurel, Miss. The larvae feed upon the tubers planted, the underground 
stems of the plants, and the crop of tubers produced. In this instance the 
larvae feed primarily upon that portion of the plant which is being grown for 
market or consumption. In many gardens 80 percent of the tubers were damaged 
to some extent and 50 percent were damaged so seriously that they were unfit 
for home consumption. In one instance the larvae killed 11 percent of the 
plants and damaged 91 percent of the tubers. Larvae burrow into and through- 
out the tubers, and it is very common to find several larvae in the same 
tuber. Where the larval population is great the major part of the contents 
of many tubers is consumed or destroyed. Strawberry plants are also serious- 
ly damaged by the larvae. 
Plants such as oats which have a fibrous root system and can be 
sewn by broadcasting or drilling during the fall or winter can withstand 
high larval populations without any appreciable damage. The grasses also 
appear able to withstand high larval populations. The larvae are not vora- 
cious feeders during the cooler parts of the year, consequently plants 
which grow and develop late in the fall and during the winter are not 
caaaged to the same extent as spring crops. 
During the fall larvae have been observed feeding on the underground 
stems and taproots of cowpeas and peanuts after these plants had matured 
and died or had been killed by frost. Evidently the decaying roots furnish 
a desirable food for the larvae. In one field the soil from around 96 
cowpea plants was examined in November 1937, and an average of 16.6 larvae 
per plant was found. An area 4 inches in diameter around each plant was 
examined to a depth of 6 inches. 
Larval dev elo pment . — The average length of the larval period as 
determined for 19 specimens was 320.5 days, or 10.7 months. These larvae 
hatched from eggs between August 4 and September 12, 1937, and became 
adults between May 24 and September 6, 1938. 
A total of 143 beetles were reared from egg to adult in outdoor 
rearing cylinders. The larvae in these cylinders hatched from the eggs from 
August 7 to December 23, 1937. The adults emerged from the cylinders from 
June 4 to August 16, 1938. The adults from larvae hatched during August 
emerged somewhat earlier than those from larvae hatched later in the season. 
The average date of emergence for beetles from larvae hatched during August 
was July 4 and the average date of emergence for beetles from larvae hatched 
in November was July 24. Some larvae which hatched during 1937, although 
apparently full-grown in 1938, did not pupate during the latter year. These 
rearing cylinders from which 143 adults emerged were examined in September 
1938 and 7 pupae and 7 larvae were found. Most of the larvae that failed 
