448 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Measurements: Largest specimen, female: length 25.7 mm, width 

 30.1 mm, rostrum (tip) 1.6 mm, width 2.1 mm, exorbital width 9.7 mm, 

 major cheliped 46 mm, merus 14.7 mm, manus 26.6 mm, dactylus 14.5 

 mm, height of palm 15.4 mm. Male specimen: length 18.6 mm, width 

 21.5 mm, rostrum (tip) 1.8 mm, width 1.75 mm, exorbital width 7.6 mm, 

 right cheliped 31.6 mm, merus 11.2 mm, manus 17.2 mm, dactyl 8.8 

 mm, height of palm 9.7 mm. 



Color in life: Carapace light cinnamon with a large purplish brown 

 spot on each side, between gastric and cardiac regions; a few scattered 

 maroon spots. Chelipeds dark pinkish cinnamon fading on fingers to 

 cream color. Ambulatory legs pale Rosellin purple, fading on dactyls to 

 cream buff. Ventral side pale gray with orange hue; last segment of 

 abdomen spotted red-purple. (Petersen, of a female from Taboga Island, 

 Panama) 



Habitat: Dredged three times on sand bottom with shell, coralline, 

 or nullipore also present, once on mud and sand bottom, and once on 

 coralline bottom. 



Depth: 2-25 fathoms. 



Size and sex: Males 7.5 to 18.6 mm, females — to 25.7 mm (smaller 

 female not found). 



Breeding: None of the females was ovigerous. 



Remarks: While examining the extensive series of specimens initially 

 referred to Parthenope (Pseudolambrus) excavata it became apparent 

 that two species, rather than one, were represented. Originally made on 

 the basis of the striking difference in the male pleopods (compare figs. 

 5 and 6 of Plate Z 2 ), the separation was supported by external morpho- 

 logical characters as well. The larger part of the series, therefore, was 

 withdrawn from Stimpson's species and is described herewith. 



Parthenope (Pseudolambrus) stimpsoni, new species 

 Plate Z, Figs. 1-6 ; Plate Z*, Figs. 6, 6a 



Type: Male holotype, Cat. No. 100919, and female allotype, Cat. 

 No. 100920, U. S. National Museum, from Secas Islands, Panama, 12 

 fathoms, February 5, 1935, Velero HI, station 448-35. For additional 

 material see below. 



Measurements: Male holotype: length 16.4 mm, width 18.6 mm, 

 rostrum 1.7 mm, width 3.0 mm, cheliped (right, major) 31.6 mm, merus 

 9.8 mm, manus 15.8 mm, dactylus 8.3 mm, height of palm 8.2 mm. 

 Female allotype: length 16.0 mm, width 19.0 mm. 



