THE TECHNOLOGIST. [Mat 1, 1865. 



442 THE CULTURE OP COTTON IN 



season, is often disfigured with unsightly yellow stains caused b} r a sort 

 of bug ; but they are easily removed by soap and w r ater, leaving the 

 cotton quite uninjured. Some people fancy these bugs to be a chief 

 cause of blight, by clustering on the pods and thus causing them to turn 

 brown, and by inserting their probosces in the sutures, so as to make 

 the valves open prematurely. I do not believe there is any ground for 

 this accusation, for the bug was just as abundant on the Egyptian cotton, 

 which did not suffer at all from blight. It is attracted by a slight 

 moisture of a sweetish mucilaginous nature, which suffuses the inner 

 lace of the valves and the outer surface of the cotton ; but it has too 

 weak a proboscis to be able to penetrate the sutures of the pod before 

 they open naturally.* 



In the valley of Piura the failing crop has sometimes been that of 

 July to September, instead of that of January to March. Possibly a 

 rapid refrigeration of the atmosphere, such as is sometimes experienced 

 after the great heats of March, may have a deleterious effect on the 

 opening flowers and ripening fruits, equally with such an augmentation 

 of temperature as we have just been taking account of. To counteract 

 that effect some people have lighted fires on the clear cold nights 

 between the rows, with the prunings of the cotton plants and other 

 rubbish, it is said with the desired result. 



The cotton-plant has other insect enemies worse than the bug. The 

 seedlings are sometimes destroyed by being cut through underground 

 by the larva of a beetle, which is probably similar to the cutworm of 

 the United States. It is fortunately rare as yet in Peru. Grillus (or 

 crickets) nip off the tops of very young plants, apparently for the sake 

 of sucking the juice. They work by night, and the holes one sees in 

 the morning recently scratched in the leaves of adult plants are also 

 probably made by crickets. But the greatest pest of this present year 

 has been a caterpillar, which has multiplied beyond all precedent, the 

 unwonted humidity having evidently favoured its increase. It 16 gene- 

 rated by a greyish moth of diurnal habits, and of very rapid repro- 

 duction. Some caterpillars I kept and fed on cotton leaves came out 

 perfect moths on the eighth day from entering the chrysalis state. 

 Caterpillars caused sad havoc in the months of February and March, 

 completely stripping the leaves from large fiats of cotton, and choosing 

 the youngest and tenderest plants first, but ending by feeding on all 

 indiscriminately. It is true the plants were not destroyed thereby ; but 

 one crop would be lost or at least retarded. No remedy has yet been 

 tried against these insects, and no bird seems to feed on them except a 



* This bug is known by tbe name of el ensartado or el arrebeteado ; because 

 the male and female are nearly always coupled. A similar hemipterous insect 

 infests the cotton on the Amazon, where it is called Piolho do algodaS, or cotton 

 louse. Mr. H. W. Bates informs me that it is a species of Dysdercv.s, of the 

 family Luja idee. 



