518 MEMOIRS OF THE CARNEGIE MUSEUM 



EXPLANATION OF PLATES. 



Plate A. 



Fig. L Cambarns obscurus Hagen. Male of the first form, natural size. Collected by the 



writer, Sept. 7, 1905, in the Alleghany River, Sandy Creek, Allegheny Cloiinty. 

 Fig. 2. Cambarns obscurus Hagen. Female, natural size. From same locality. 

 Fig. 3. Cambnrus diogenes Girard. Male of the first form, natural size. Collected by the 



writer, Aug. 26, 1905, at Baden, Beaver County. 

 Fig. 4. Cambarns carolinus Erichson. Female, natural size. Collected by the writer, Sept. 5, 

 1905, at Rainier Park, Ohiopyle, Fayette County. 



Plate B. 

 Fig. 1. Cambarus bartoni (Fabricius). Male of first form, natural size. Collected by the 



writer, Aug. 7, 1905, in Fern Hollow, Pittsburgh. 

 Fig. 2. Cambarus barton! robustus (Girard). Female, natural size. Collected by Miss G. 



Kinzer, Aug. 27, 1905, at Sixteen Mile Creek, Northeast, Erie County. 

 Fig. 3. Cambarus limosus (Rafincsque). Female, natural size. Collected by the writer, Sept. 



10, 1905, in the Schuylkill Canal, Manayunk, Philadelphia County. 

 Fig. 4. Cambarus monongalensis Ortmann. Female, natural size. Collected by the writer, 



Aug. 18, 1905, at Edgewood Park, Allegheny County. 



Plate XXXIX. 

 Fig. 1. Cambarus bartoni (Fabricius). Rostrum. All figures ^. 



la. Female, 70 mm. long. Collected by the writer, June 3, 1904, in North Versailles 

 Township, Allegheny County, opposite Stewart. Catalogue number 74.327. Shape 

 very broad, margins parallel. Not rare in western Pennsylvania. 



lb. Female, 52 mm. long. Collected by the writer, Aug. 22, 1905, at Squaw Run, Alle- 

 gheny County. Catalogue number 74.626. Shape typical ; very frequent. 



le. Male, first form, 63 mm. long. Collected by the writer, Sept. 16, 1904, at Valley 

 Forge, Chester County. Catalogue number 74.413. Shape typical, and character- 

 istic of eastern specimens, but also found in the west. 



If?. Young male, second form, 34 mm. long. Collected by the writer, Aug. 22, 1905, 

 in Squaw Run, Allegheny County. Catalogue number 74.626. Usual shape in 

 young specimens. 



le. Young female, 21 mm. long. Collected by the writer, June 25, 1904, in Jacob's 

 Creek, Laurelville, Fayette County. Catalogue number 74.356. Slightly longer 

 than usual, but not rare in young specimens. 



1/. Male, first form, 78 mm. long. Collected by the writer, May 27, 1904, in Squaw Run, 

 Allegheny County. Catalogue number 74.320. Unusually short and strongly taper- 

 ing, with exceptionally thick margin. 



