A NEW PHYLLOPOD—MACKIN' 37 
Pontotoc County, Okla., which attain a length of 23 mm. This is the 
same pond from which Creaser (1930) reported large specimens of S. 
seali (36.2 mm.). 
Localities. —The following records are placed in approximate posi- 
tion on the map (fig. 6). There are 14 collections of S. dorothae, all 
in New Mexico except 2 in the far western edge of the Texas Panhandle 
and 2 in the western end of the Oklahoma Panhandle. [or comparison 
all records of S. texanus are also shown; 27 of these are collections and 
identifications by the author, and the previous records as shown by 
Creaser (1930) are added. The greatest concentrations of S. dorothae 
are in the short-grass prairic, close to the Rocky Mountain foothills, 
while the most favorable ecological conditions for S. texanus seem to be 
farther east in the long-grass areas. All collections of S. dorothae have 
been taken in August, but this means only that collecting trips are 
most feasible during that month, and I have not been able to make 
such trips at any other time. The date plus the additional number 
constitutes the author’s accession number, 
8-12-28+-1, 8 miles west of Summerfield, Parmer County, Tex. 
8-18-36-+-3, 1 mile west of Turpin, Texas County, Okla. 
8-18-36-+-4, 12 miles east of Boise City, Cimarron County, Okla, 
8-19-36-+6, 2 miles west of Capulin, Union County, N. Mex. 
8-19-36-+-7, 10 miles west of Capulin, Colfax County, N. Mex. 
8-19-36-+-8, 10 miles southeast of Raton, Colfax County, N. Mex. 
8-19-36-+-10, 3 miles south of Raton, Colfax County, N. Mex. 
8-20-36+-11, 20 miles south of Santa Fe, Santa Fe County, N. Mex. (type 
locality). 
8-20-36-4-12, 35 miles northwest of Encino, San Miguel County, N. Mex. 
8-21-36-+14, 12 miles northeast of Vaughn, Guadalupe County, N. Mex. 
8-21-36-+-15, 100 meters east of New Mexico-Texas line, on Highway 66, 
Deaf Smith County, Tex. 
8-27-38+-3, 10 miles east of Raton, Colfax County, N. Mex. 
8-27-38 +-1, 20 miles east of Colfax, Colfax County, N. Mex. 
8-27-38+-2, 5 miles southeast of Raton, Colfax County, N. Mex. 
Remarks.—Not much is known concerning the ecology of the species 
of Streptocephalus. All North American species prefer clear water with 
abundant vegetation, and the largest populations occur in such habi- 
tats, although all three species are tolerant of high turbidities and 
limited food supply. All collections are from temporary ponds, or, in 
some cases, the large prairie “lakes’’ with widely fluctuating water 
level. I have on two occasions collected S. dorothae and S. texanus 
in the same pond at the same time. Both of these were collections 
from near Raton, N. Mex. (8-19-36+-8 and 8-27-38-+-3). 
Characters of S. texanus have been shown in contrast with S. 
dorothae in the text of the description and in figures 4 and 5. The 
species are undoubtedly closely related. 
Cotypes.—In. the collection of the U. S. National Museum (No. 
79019) and in the collection of the author. 
