626 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 113 
d 
ovig. 2?- 2.4mm. 
h 
ovig. ?- 3.5mm. b 
¢- 6.8mm. ovig.2- 5.0mm. 
Ficure 4.—Calcinus explorator Boone, left chelae, X 4.8, of specimens having anterior 
carapace lengths as indicated. 
as indicated by Holthuis (1954, p. 22, figs. 5 and 6). Unfaded material 
of C. obscurus in the U.S. National Museum corresponds very well 
with Holthuis’s description and figures. Likewise, comparison of 
Clipperton specimens with Galapagos material in which the color 
pattern is still visible verifies the identity of those two forms. 
Although the morphological characters cited by Boone (1932) to 
distinguish C. explorator from C. obscurus are too variable to be valid, 
the broad orange bands on the dactyls of the walking legs in Galapagos 
specimens were noted by both Schmitt (1927) and Boone. C. explo- 
rator may eventually prove to be a subspecies of OC. obscurus, but 
the absence of intermediate color forms in the material at hand suggests 
that the two are specifically distinct. Color patterns seem to be more 
constant and reliable than morphological characters in the genus 
Caleinus. 
For differences between C. explorator and C. californiensis, see 
the remarks under the latter species. 
Distrisution: Previously recorded from the Galapagos and Cocos 
Islands, but the latter locality needs verification. Specimens from 
Socorro Island, Mexico, in the U.S. National Museum also belong to 
this species, but material from Cocos and Clarion Islands has lost 
all traces of the color pattern and cannot be positively identified. 
