PACKARD. ] PHYLLOPODS OF NORTH AMERICA. 347 
these were supposed to represent a different species and described in the 
Bulletin of Hayden’s U.S. Geological Survey of the Territories in 1877. 
Since then I have received a number of specimens from Wallace, Kans., 
through Professor Lindahl, some of which. were of the same size and 
state of preservation as the Texan specimens, and which showed no 
specific differences, and finally, on carefully examining and drawing 
the feet of specimens from the two States, I found that they could not 
be separated specifically. 
I append the description of the Kansas specimens from Hayden’s 
Bulletin, which may show bow the individuals vary, especially in the 
male claspers: 
‘¢ Male.—The claspers (2d antennz) are much longer than in S. texanus, 
reaching, when extended, to the middle of the body, while in S. texanus 
they only reach a third of the length of the body. The median lobe of 
the head, which is very large and long in S. teranus, reaching nearly as 
far as the insertion of the basal filamentary appendage of the third 
joint of the claspers, is, in S. watsoni, not half as large. The two basal 
joints of the claspers are twice as long and much slenderer than in VS. 
texanus ; the third joint is nearly as long, while the branches and spines 
of the 4th joint, though of the same number, are much longer and slen- 
derer. Of the longer branch the supplementary spine is much longer, 
and without the small inner spine, while the main branch beyond is bent 
at right angles, the elbow being much bent, the inside, however, regu- 
larly curved. At the base of the broader and shorter branch are four 
unequal teeth; one attached to the third joint, the other to the fourth, 
the two terminal ones very unequal, and the fourth square and three times 
as large as the third, while the corresponding tooth in S. texanus is long 
and narrow, and smaller than the one behind it. The genital appendages 
are long and slender, much as in S. tevanus, being as long as the three 
segments following the one to which they are inserted. The caudal ap- 
pendages are much shorter and broader than in S. texanus, each blade 
being broader, and tapering regularly from base to tip, not contracted 
in the middle, nor curved, as in the male of S. texanus ; on the other 
hand, they are of much the same form as in those of the female S. texa- 
NUS. 
** Female.—Very closely allied to the female S. texanus, though as a rule 
somewhat smaller, the eyes being decidedly smaller. ‘The second an- 
tenne are a little, sometimes much, longer in proportion, and are mu- 
cronate, as in the other species. The ovisacs are as in WN. fexanus, but 
the eggs are much smaller in proportion. The caudal appendages do 
not differ materially from those of the males, nor from those of the 
females of S. texanus. 
‘Length of males, 16™™; females, 12-18™™. About fifty of each sex 
examined, although several hundred were casually looked over, with- 
. out finding any that approached WN. tevanus any nearer than has been 
indicated. 
“ Hillis, Kans., in pools on the prairie, June 28, 29, September 27, and 
October 10-22, Dr. L. Watson. <A large number of half-grown males 
and females occurred in June. The largest females, those measuring 18 
millimeters in length, occurred October 22, the ovisacs filled with eggs 
in some cases; in others, partially or entirely empty. The body was 
soft and in such a state of preservation as to indicate that they were at 
the point of dissolution. They were found associated with Thamno- 
cephalus, Limnetis, Estheria, Bulimnadia, and Apus lucasanus. The tails 
were red, says Dr. Watson, and in some the bodies were blue. This re- 
ters to those which were collected in June and early in July. ‘Those 
