24 PLANT-BUGS INJURIOUS TO COTTON BOLLS. 
with the note that the species was injuring cotton in the Laguna 
District of Mexico at San Pedro de la Colonia, State of Coahuila. 
In March, 1904, the author was directed by the Entomologist to in- 
vestigate a reported partial destruction of the cotton crop by an un- 
known pest in the Laguna District of Mexico. The specific report 
emanated from a large plantation of between 25,000 and 30,000 acres 
of cultivated land located in the northern portion of the Laguna 
District, the headquarters being at Tlahualilo, State of Durango. 
At the season of the year when the first visit was made, although the 
cotton stalks were still standing in the fields, it was impossible to 
establish positively the relationship between the conchuela and the 
large number of ruined bolls present everywhere on the plantation. 
The second visit to Tlahualilo from August 30 to September 8, 1904, 
resulted in this point being definitely determined as well as in the 
procuring of considerable information concerning the insect and its 
work. The details of these preliminary investigations were reported 
on in a previous bulletin of this Bureau. 
The investigations were continued in 1905 at Tlahualilo, where the 
author of this report spent the month of July and a week in the early 
part of December. 
The conchuela has recently become known as a pest in western 
Texas, where, in 1904 and 1905, near Barstow, it occasioned con- 
siderable loss to seed crops of alfalfa, and in the latter season proved? 
in addition, its destructiveness to miscellaneous crops, including 
peaches, grapes, peas, and other garden products. The report of the 
investigation of this unexpected outbreak has been published under 
a separate title. 6 
DISTRIBUTION. 
The distribution of Pentatoma ligata is a wide one, the species 
occurring rarely in the eastern half of the United States, and with 
much more frequency in the arid and semiarid regions of the Western 
States and Mexico. It is probably of considerable significance that 
hitherto localities where this species has been found to occur in large 
numbers have been situated in the Lower Sonoran faunal region of 
the Lower Austral zone. In Texas miscellaneous collections for three 
years by members of the Bureau of Entomology engaged in cotton 
boll weevil investigations have not included a single specimen of 
Pentatoma ligata taken east of the semiarid region or approximately 
the ninety-eighth degree of longitude. A single specimen in the 
collection at the office of the Texas state entomologist bears the 
label Beeville, Tex., which is situated between the ninety-seventh 
and the ninety-eighth degrees of longitude and is the easternmost 
a Bui. 54, Bur. Ent., U. S. Dept. Agr., pp. 18-34, 1905. 
6 Bui. 64, Pt. I, Bur. Ent., U. S. Dept. Agr., 1907. 
