462 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



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 fire, while the air was filled with them, as it is with 

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

 make their first appearance as saltones, 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 filled 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 rivers and drowned. Various expedients 

 are resorted to by the owners of plantations to prevent the passing columns from alight- 

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

 making a noise put in requisition for the purpose. In this mode 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 cliapulin 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- 

 thiDg 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 from 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 1632." In 1855 the valley of Colima, in Southwestern 

 Mexico, was visited by locusts. 



In 1856 their ravages extended along the mesas or steppes border- 

 ing 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 Yera Cruz, 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. 



We have received from Signor Manuel Medina, of Merida, Yucatan, 

 the following answers to our circular, the numbers corresponding to the 

 numbers appended to the questions in our circular: 



1. The swarms of locusts which appeared some nine miles from the sea-shore, were 

 suddenly discovered in June, 1871, in great quantities, living on the leaves of the 

 Agave sisalense in plantations covered wholly with this plant. It could not be ascer- 

 tained whence they came, but surely they began to be noticed by that time not far 

 from the port called Progreso. They began to migrate, flying always toward the south, 

 the wind blowing, from the spot whence they started, in a northeast direction. The 

 temperature was then very warm, say 87° to 90°, the mornings being lightly moist 

 and cloudy, but the rest of the day very clear. The density of the swarms flying 

 when started was not of great consideration, migrating in comparative small portions. 

 They did not invade the whole province, but only a portion of the country from north 

 to south on a breadth of 40 or 60 miles. 



2. The date of departure is that of its discovery, when started by the exertions of men, 

 in June. The force of the wind was always not hard, but in a southeast direction . The 



