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PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 75 



found it not only at Lincoln but at Omaha and in Cherry County, 

 and in Council Bluffs, Iowa. Schacht, 1897, and later, Stromsten, 

 1920, reported it from the Okoboji Lakes in Iowa. Dodds, 1908, 

 1915», 1917, 1920, 1924, found it in Palmer Lake and La Junta, Colo. 

 The writer has found it in Colorado at Hugo and in lakes about 



Pikes Peak ; in Gunnison Reservoir, Utah ; 

 at Los Angeles, Calif. ; in Devils Lake, N. 

 Dak., in collections made by Young; in 

 Big Stone Lake between South Dakota 

 and Minnesota; in Cedar Lake, Wis.; in 

 a collection made by Shelford at Medora, 

 Kans., in Turkey Lake and at Hammond, 

 in Indiana; in Creve Coeur Lake and 

 other localities near St. Louis, Mo. ; and 

 in a collection made by Birge at Hutch- 

 ins, Tex. Juclay, 1915, collected it at 

 Coatepeque and Lake Ilopango, San Sal- 

 vador, and it was found in a collection 

 made by Hildebrancl in Lake Chamico, in 

 San Salvador. It has not been found 

 north of the United States. Figure 10 

 shows its distribution. 



DIAPTOMUS SIGNICAUDA Lilljeborg, 1889 



In the description of this species it was 

 said to have been collected in the Sierras, 

 Calif. It Avas found in collections made 

 by C. F. Baker in Marlette Lake, Nev., 

 and in collections made by H, B. Ward in 

 several small lakes near Lake Tahoe. It 

 was contained in material gathered by 

 Juday in Hocketts Lakes, Calif., and 

 Boulder, Colo. Stromsten, 1917, noted 

 its occurrence in the Okoboji Lakes 

 in Iowa, and the writer found it in Wheat Meadows and Duck 

 Lake in Calaveras County, Calif. Its distribution is shown in 

 Figure 12. 



DIAPTOMUS SPATULOCRENATUS Pearse. 1906 



Pearse found IJ. spatulocrcnatus on Nantucket Island. The writer 

 found it in a collection made by A. A. Doolittle from Lake Sebago, 

 in Maine. In a comparison of the Lake Sebago material with the 

 original description certain minor differences were noted. The 

 presence of lateral spines on the first abdominal segment of the 

 female was not mentioned by Pearse. The second basal segment of 



Figure 11.— Diaptomus spatulocre- 

 NATU3 Pearse, fifth left foot of 

 MALE, X 424 



