[62] REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
and clear, dewy nights during those months seem to protect the plantations against 
the lavages of this insect. The Mexican farmers, aware of this fact, have given the 
holl worm the name of " Chahuistle," which is an Indian word for cloudy, misty 
weather. 
The damage caused by this worm on new lands is small ; also on old lands where 
the plant has been set wide apart, say from 8 to 9 feet. 
I therefore draw from these observations the following conclusions, viz: The larve 
deposited by the moth on the ground remains there from eight to nine months, 
the young worm appearing just at the time when the cotton plant throws out the 
bolls 1 . 
Plowing and thorough tilling should be a preventive against this worm. Sunny 
weather destroys it. Setting the plants wide apart, at least 6 feet, would allow the 
sun to heat the ground, and must be, in my opinion, beneficial. 
The larger worm, or caterpillar (Anomis xylina) has made its appearance on this 
coast three times during the last twenty years ; in 1866, in 1873, and again in 1878. It 
is a dark-green looping worm, with white and black lines, and destroys the cotton 
plant by devouring the leaves. It is as yet impossible for me to find out the origin 
or even habits of this worm. I have investigated the supposed causes of its appear- 
ance, but without success ; the farmers here have not the slightest idea about it. An 
apparent coincidence between the appearance of this plague and overflooding of rivers 
in the cotton regions should be mentioned here. 
September, 1^65. High floods : complete inundation of cotton lands. 
February, 1866. Appearance of the caterpillar in small numbers, not causing much 
damage. 
September, 1872. Floods ; partial inundation of cotton lands : high lands and ridges 
in the valleys not flooded. 
February, 1873. Appearance of the plague and total destruction of cotton planta- 
tions. 
September, 1878. High floods ; complete inundation of cotton-growing valleys. 
February, 1879. Partial plague ; small damage done by the caterpillar. 
4. In answer to question 4 I would refer to above statements. I draw from them 
the opinion that the worm has not been imported into Mexico, but originates in the 
cotton valleys in such seasons when the peculiar condition of the soil and climate 
combine to favor the development of larves brought down by floods from the moun- 
tain lands. 
The cotton lands in this vicinity are bounded on the west by the Pacific Ocean, on 
the east by high mountains, la ; ' Sierra Madre: " on the north and south by dense 
woods and tracts of uncultivated lan^s. These circumstances present a great many 
obstacles to the flight of the cotton moth. The nearest cotton plantations, as well to 
the northward as to the southward, are at a distance from Manzanillo of at least 100 
miles. 
Cotton has been grown in the State of Colima for the last fifty years. It does not 
grow wild, but, if abandoned, some plants grow up to good-sized trees, bearing fruit 
regularly every year. 
6. The directions of prevailing winds on this coast are the following, viz: January, 
south and west ; February, west and northwest ; March, west and northwest ; April, 
northwest; May, northwest; Juue, south and northwest; July, south and west; Au- 
gust, south and west ; September, south and west ; October, south and west; Novem- 
ber, south and west ; December, south and west. 
The northwest and west winds blow generally during the day ; at night these winds 
change to the north and northeast. 
I give the prevailing winds for the whole year, as our planting and picking seasons 
here are different from those in the United States. 
7. It is not possible for me at present to remit specimens of insects that attack the 
cotton plant, but reserve myself the privilege to do so in February next— the time 
when these different insects make their appearance here. 3 * 
I am, sir, vour obedient servant, 
AUGUSTUS MORRILL, 
United States Consul. 
Hon. William Hunter, 
Second Assistant Secretary of State, Washington, D. C. 
No. 77.] Consulate of the United States, 
MazatJan, December 3, 1879. 
Sir : I beg to respectfully acknowledge receipt of communication dated October 13, 
1879, inclosing a copy of a letter from the Chief of the Entomological Commission 
addressed to t he Honorable the Secretary of the Interior, under date of October 6, 1879, 
* No specimens received. — C. V. R. 
