120 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Diagnosis: Rostral spine moderately long, terminally bifid. A promi- 

 nent, laciniate, postorbital spine. Hepatic and pterygostomian regions 

 tipped with a cylindrical spine. First ambulatory leg between two and 

 a half and three times length of carapace, its dactylus not quite one- 

 third propodal length. Two median tubercles on first abdominal seg- 

 ment. Dactylus of fourth leg two-thirds propodal length. Male manus 

 inflated, one tooth in gape. Curved hair count 14. Galapagos only. 



Description: Carapace smooth, pyriform, elevations separated by 

 shallow grooves. One cardiac and one gastric tubercle; in front of the 

 latter a smaller tubercle. Gastric region smooth, rounded, bearing four 

 tufts of setae arranged in a rectangle. Branchial regions flattened, 

 traversed by a longitudinal row of curved setae. Hepatic and ptery- 

 gostomian regions tumid, each bearing a short, cylindrical spine. 

 Rostrum acuminate, tip bifurcate, length equal to one-fourth post- 

 rostral portion of carapace. Orbits spinulous; postorbital spine large, 

 outer margin laciniate. 



Basal antennal article narrow, externally spinulous, internally bear- 

 ing a compressed ridge. Antennae long and slender, second movable 

 article reaching tip of rostrum. Merus of third maxilliped with inner 

 angle produced into a thin, triangular blade. Segments of male sternum 

 deeply separated; two prominent tubercles at base of chelipeds. First 

 abdominal segment bearing two median setose tubercles. 



Chelipeds of male robust, hairy, and spinulous. Merus trihedral, 

 curved lower margin armed with spines. Palm inflated, roughened, 

 spinules in rows; fingers gaping broadly at basal half, a prominent 

 tooth on movable finger. First ambulatory leg equal to two and one- 

 half times the length of carapace, including rostrum, its dactyl straight 

 and approximately one-third the propodal length. Second ambulatory 

 little more than half the length of the first, third and fourth legs 

 subequal ; dactyls of legs two, three, and four falcate and from one-half 

 to two-thirds the length of their respective propodi. 



Female chelae slender, fingers almost meeting when closed, finely 

 dentate, curving inward. First ambulatory leg twice the length of the 

 carapace. 



Material examined: 20 specimens from 10 Galapagos stations (see 

 Garth, 1946, p. 371). Darwin Bay, Tower Island, Galapagos, shore, 

 February 24, 1933, Velero III station 97-33, 1 young male. 



Measurements: Male holotype: length 12.8 mm, width 7.9 mm, 

 rostrum 2.8 mm, width 1.4 mm, cheliped 14.6 mm, chela 6.1 mm, 

 dactyl 3.3 mm, first ambulatory leg 34 mm, propodus 12 mm, dactyl 



