1892.] The Striped Harvest-Spider. 999 
THE STRIPED HARVEST-SPIDER: A STUDY IN 
VARIATION. 
By CLARENCE M. WEED. 
In 1821 Thomas Say described in the Journal of the 
Academy of Natural Sciences of Philadelphia two species of 
harvest-spiders, one of which he named Phalangium vittatum 
and the other Phalangium dorsatum. He stated that the 
former “inhabits the Southern States” and that the latter 
“inhabits the United States.” His descriptions in both cases 
were evidently drawn up from specimens not fully matured, 
and the characterizations are meagre and unsatisfactory. The 
two species are said to be similar in color, but distinguished 
from each other by the “terminal joint of the palpi being 
pectinated with spines” in P. dorsatum. 
In 1868 Dr. H. C. Wood published extended descriptions of 
both these species! He states that they are closely related, 
“the principal characters separating the two being found in 
the differences in coloration of the dorsum and legs, the tro- 
chanter not being black in P. vittatum, and the much greater 
hardness and roughness of the upper surface of the southern 
species.” He adds that P. vittatum “may be looked upon as 
the southern representative of its nearest ally, P. dorsatum, of 
which I have never seen any specimens from farther south 
than Washington City. ” 
Since Dr. Wood’s paper was published I have treated of? 
these species two or three times, taking them out of the old 
genus Phalangium, and referring them to Liobunum. In 1889 
I stated that “after examining hundreds of specimens of 
dorsatum and dozens of vittatum, I am unable to find any con- 
stant structural character by which they may be separated, 
though the difference in the size of the body and length of legs 
is very marked. ” 
*Comm. Essex Institute, VI, pp. 18-21. 
"AMER. NAT., XXI, p. 935; Bull. Ill. St. Lab. Nat. Hist. III, pp. 83-87. 
