STRIPED SOD WEj^WORM, CRAMBUS MUTABITIS 
CLEMENS' 
By Gkorge G. AinsuiS 
Entomological Assistant^ Cereal and Forage Insect Investigations, Bureau of Entomology, 
United States Department of Agriculture 
INTRODUCTION 
Throughout a wide area Crambus mutahilis is one of the most common 
species of the genus. It ranks well toward the head of the list in de¬ 
structiveness, although by itself it never has been directly charged with 
a destructive outbreak. It has not previously received detailed study, 
and the available information concerning it is scattered and meager. 
The present paper includes a summary of previously published facts, 
together with the results of the writer’s studies for several years. 
SYSTEMATIC HISTORY 
Crambtis mutahilis was first described by Clemens (j, />. 20^^ in i860, 
but he furnished no information as to the source of his material. Three 
years later Zeller p, 44) redescribed it as Crambus fuscicostellus, a 
name which better characterizes the species than Clemenses adjective. 
Both names appear in the literature for some years, although Grote 
(7, p, 79) early recognized their probable synonymy. Smith (/ j, p. 87) first 
placed fuscicQsteUus unconditionally as a synonypi of mutahilis, in which 
he is fully borne out by Hampson {8, p. p28), who hafi Zeller’s type in the 
British Museum for comparison. 
GEOGRAPHICAL DISTRIBUTION 
Crambus wi^toWwseeips to be a purely North American species, for out¬ 
side of North Anieripa it jbas he^u reported only by Hedemann, (9,/>. 300), 
from St. Thqma^ Island in the T^^st Indies It is widespread over the 
eastern half w $he United States. A study of the published records and 
of all the ayaijable museum material ^ows that the ouJly^ng points from 
which reliable records are available sixo, Bro wn s v ille arm Amarillo, Tex.; 
Vineyard, Utah; Sioux City, Iowa; and Cartwright, Manitoba. It has 
been found in most of the States to the eastward of a line connecting these 
places, although it does not appear in a considerable collection of the 
genus made in southern Minnesota, and has not been recorded from 
Wisconsin, West Virginia, and several of the New England States. 
The reported occurrence in Nebraska is evidently based on Bruner’s 
paper {2, p. 262), in which, however, he does not say that it has been 
taken in that State. It has been taken at numerous points in Florida, 
but,except fora single specimen from northwestern Arkansas,has not yet 
been reported from the tier of States between and including Oklahoma 
^ Accepted for publication July ix, 1922. This paper is the third in a series of Contributions to a Knowledge 
of the Crambhiae of North America. I, Crambus hemiochreUus Z^er. ^ppear^ in Annals of the Entomo¬ 
logical Society of America for March, 1918, and II, Crambus lagueatelfus Clemens, in the Jtme, 1932, issue 
of the same journal. 
2 Reference is m^e by number (italic) to “literature cited, p. 4x4. 
Vol. XXIV, No. 5 
May s. 1923 
Key No. K-xo6 
Journal of Agricultural Research, 
Washington, D. C. 
adn 
( 399 ) 
