648 PEPORT UNITED STATES GEOLOGICAL SURVEY. 



vals afflicts the entire country, passing from one end to the other in vast colnnma of 

 many luillions, literally darkening the air and destroying every green thing in their 

 course. I once rode through one of these columns which was fully ten miles in width. 

 Not only did the insects cover the ground, rising in clouds on each side of the mule- 

 path as I advanced, but the open pine-forest was brown with their myriad bodies, as 

 if the trees had been seared with tire, while the air wa^ tilled with them, as it is wijh 

 falling flakes in a snow-storm. Their course is always from south to north. They 

 make their first appearance as sallones, of diminutive size, red bodies, and wingless, 

 when they swarm over the ground like ants. At this time vast numbers of them are 

 killed by the natives, who dig long trenches two or three feet deep, and drive the sal- 

 tones into them. Unable to leap out, the trench soon becomes half tilled with the young 

 insects, when the earth is shoveled back, and they are thus buried and destroyed. 

 They are often driven in this way into the ris-ers and drowned. Various expedients 

 are resorted to by the owners of ])lantatiou8 to prevent the passing columns from alight- 

 ing. Sulphur is burned in the tields, guns are tired, drums beaten, and every mode of 

 making a noise put in requisition for the purpose. In this niode detached plantations 

 are often saved. But, when the columns once alight, no device can avail to rescue 

 them from speedy desolation. In a single hour, the largest maize-fields are stripped of 

 their leaves, and only the stems are left to indicate that they once existed. 



It is said that the chapuUn makes its appearance at the ends of periods of about fifty 

 years, and that it then prevails for from five to seven years, when it entirely disappears. 

 But its habits have never been studied with care, and I am unprepared to affirm any- 

 thing in these respects. Its ordinary size is from two and a half to four inches in 

 length, but it sometimes grows to the length of five inches. 



Mr. Taylor remarks that " this statement is consonant with the 

 accounts received irom Honduras and Guatemala of the famine and 

 pestilence of fever in those countries in 1855 and 1856, caused by clouds 

 of locusts devastating the country, and confirms Gage's history of the 

 same lands in 1032." In 1855 the valley of Colima, in Southwestern 

 Mexico, was visited by locusts. 



In 1850 their ravages extended along the first central mesas or steppes 

 bordering eastward the Eocky Mountains, covering the dry soils of 

 Texas, and down into the south of Mexico. In the vicinity of Cordova, 

 in the State of Vera Crnz, the people made a regular campaign against 

 them, and succeeded in destroying one hundred and ninety-two arrobas, 

 computed as numbering four hundred million grasshoppers. In the 

 State of Guerrero they also did great injury, particularly within the dis- 

 tricts around Acapulco. 



The treeless i)ortions of South America are also not exempt from 

 swarms of locusts, though we have no information as to the different 

 species composing them. Taylor says that at the time of the visit of 

 Darwin to Chile and the adjacent countries of South America he relates 

 of the grasshoppers as follows, at the date of March 25, 1835, when he 

 was crossing the dry country which lies between the city of Mendoza, in 

 Buenos Ayres, and the opposite side of Chile. This counti\v assimi- 

 lates in every essential physical characteristic to that of the territories 

 within the boundaries of Upper and Lower California prior to the 

 American occupation : 



"Shortly beiore arriving at the village and river of Lnxan, we ob- 

 served to the south a ragged cloud of a dark reddish brown color. At 

 first we thought it was caused by some great fire on the neighboring 

 plains, but we soon found thar it was a swarm of locusts. They were 

 flying northward, and with the aid of a light breeze they overtook us at 

 the rate of ten or fifteen miles an hour. The main body filled the air 

 from a heiglit of twenty feet to that, as it api)eared, of two or three 

 thousand feet above the ground. The sound of their wings was as the 

 sound of chaiiots of many horses running to battle; or rather, as I 

 should say, like a strong breeze passing through a ship's rigging. The 

 sky, seen through the advanced guard, appeared like a mezzotiuto 

 engraving; but the main body was impervious to sight. They were not, 



