120 ORTMANN — AFFINITIES OF CAMBARUS. [April 13, 
KEY TO THE SPECIES OF THE SUBGENUS BARTONIUS. 
1. Section of C. hamulatus (see p. 118). 
Rostrum with marginal spines. Areola wide. 
iG: (Bartonius) hamulatus (Cope and Pack. ). 
Rostrum without marginal spines (rarely with spines in the young). Areola 
narrow. C. (Bartonius) setosus Fax. 
a 
2 
i 
n 
to 
Section of C. extraneus (see p. 118). 
NS 
a, Antennz with normal flagellum. 
6, Rostrum concave above. Areola rather wide. 
C. (Bartonius) extraneus Hag. 
6, Rostrum flat above. Areola narrower. C. ( Bartonius) jordani Fax, 
a, Antenne with very long, compressed flagellum, which is ciliated on the inner 
side. C. (Bartonius) cornutus Fax. 
3. Section of C. bartont (see p. 119). 
a, 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. 
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. 
6, Areola rather wide. Chelze smooth, punctate, inner margin of palm with 
one or two rows of tubercles. 
c, Fingers of chelze broad, slightly gaping at base, not bearded. 
C. (Bartonius) bartoni (F.). 
c, Fingers of chelze subcylindrical, widely gaping at base, the outer one 
bearded at base. C. (Bartonius) longulus Gir. 
6, Areola narrower. Chelz rough or tuberculated. 
C. (Bartonius) latimanus (Lec. ). 
Q 
a 
4. Section of C. diogenes (see p. 119). 
a, Areola very narrow, but not obliterated. Color very striking. 
6, Rostrum broad, Outer margin of hand serrate. Color red. 
C. (Lartonius) carolinus Er. 
6, Rostrum narrower. Outer margin of hand not serrate. Color blue. 
C. (Bartonius) monongalensis Ortm. 
a, Areola obliterated in the middle. Color dull, greenish or brownish. 
4, Rostrum concave above. 
c, Fingers of chelze not remarkably flattened, the inner one without dis- 
tinct excision at base, the outer one not bearded, 
C. (Bartonius) diogenes Gir. 
¢,.Fingers of chelz flattened, the inner one with distinct excision at 
base, the outer one bearded. C. (Bartonius) argillicola Fax. 
4, Rostrum flat above. C. (Bartonius) whleri Fax. 
