120 ORTMANN — AFFINITIES OF CAMBARUS. [April 13, 



KEY TO THE SPECIES OF THE SUBGENUS BARTONIUS. 



i. Section of C. hamulatus (see p. 118). 



a x Rostrum with marginal spines. Areola wide. 



C. (Bartonius) hamulatus (Cope and Pack.). 



a 2 Rostrum without marginal spines (rarely with spines in the young). Areola 



narrow. C. (Bartonius) setosus Fax. 



2. Section of C. extraneus (see p. 118). 



tfj Antennae with normal flagellum. 



b x Rostrum concave above. Areola rather wide. 



C. (Bartonius) extranius Hag. 



b 2 Rostrum flat above. Areola narrower. C. (Bartonius') jordani Fax. 



a 2 Antennae with very long, compressed flagellum, which is ciliated on the inner 



side. C. (Bartonius) cornutus Fax. 



3. Section of C. barton i (see p. 119). 



flj Rostrum long, tapering from base to tip. Areola very wide and short, a little 

 shorter than half of the anterior section of carapace. Carapace with lateral 

 spines. C. (Bartonius) acuminatus Fax. 



a 2 Rostrum shorter, suddenly contracted to a short acumen. Areola moderately 

 wide or narrow, distinctly longer than half of the anterior section of cara- 

 pace. Carapace with or without lateral spines. 



b x Areola rather wide. Chelae smooth, punctate, inner margin of palm with 

 one or two rows of tubercles. 

 c x Fingers of chelae broad, slightly gaping at base, not bearded. 



C. (Bartonius) bartoni (¥.). 

 c 2 Fingers of chelae subcylindrical, widely gaping at base, the outer one 

 bearded at base. C. {Bartonius) longulus Gir. 



b 2 Areola narrower. Chelae rough or tuberculated. 



C. (Bartonius) latimanus (Lee). 



4. Section of C. diogenes (see p. 119). 



«! Areola very narrow, but not obliterated. Color very striking. 

 b l Rostrum broad. Outer margin of hand serrate. Color red. 



C. (Bartonius) carolinus Er. 

 b 7 Rostrum narrower. Outer margin of hand not serrate. Color blue. 



C. (Bartonius) monongalensis Ortm. 

 a 2 Areola obliterated in the middle. Color dull, greenish or brownish. 

 b x Rostrum concave above. 



c x Fingers of chelae not remarkably flattened, the inner one without dis- 

 tinct excision at base, the outer one not bearded, 



C. (Bartonius) diogenes Gir. 



c s Fingers of chelae flattened, the inner one with distinct excision at 



base, the outer one bearded. C. (Bartonius) argillicola Fax. 



/>., Rostrum flat above. C. (Bartonius) uhleri Fax. 



