NO. 3 GARTH : SOME NEW SPECIES OF BRACHYURAN CRABS 75 



reduction" (Rathbun), a condition suggestive of the almost un- 

 reduced teeth of Portunus (P.) as per. 

 (7) The frontal teeth are equal and bluntly triangular instead of 

 the outer pair being less triangular than the inner. 



There is no particular in the Stimpson description not met in full 

 by the species in question, which is as distinct from panamensis as both 

 are from asper. One might desire that Stimpson had expatiated upon 

 the extreme fragility of the carpus and manus, yet the words "very 

 slender" convey the meaning now that additional specimens are at hand. 

 Also, the extreme attenuation of the lateral spine, encompassing all but 

 one, or in rare cases, all the lateral spines except the exorbital, might 

 have been more forcibly called to attention. This was indicated by Stimp- 

 son in the designation acuminatus, but the meaning of the name perished 

 with his specimen, to be recovered with ours. 



In an attempt to account for the Stimpson species, Miss Rathbun has 

 successively applied the name acuminatus to the most likely specimens 

 among the meager assortment of Pacific Portunus at her disposal. Her 

 Portunus (P.) acuminatus (1910) from Sechura Bay, Peru, was later 

 referred by her to P. panamensis (1930) in the light of the above-men- 

 tioned specimen 40270, which, while not in complete agreement, as 

 noted by her, fitted the description better than the Peruvian specimens. 

 The writer follows the same logic in abandoning her specimen 40270 

 as acuminatus in consideration of the large series of Hancock Expedi- 

 tion specimens which fit Stimpson's description precisely. One of these, 

 a male of identical dimensions, has been selected to replace Stimpson's 

 type, which perished in one of a series of disasters which decimated his 

 collections. 



A key to the identity of the Rathbun specimen is found in the fact 

 that on the strength of it she considered acuminatus, panamensis, and 

 asper as possible forms of a single species. Its measurements preclude the 

 possibility of its being the relatively narrow panamensis ; hence it is 

 probably an asper, the lateral spine of which has the maximum attenua- 

 tion. Similar specimens are found in the Hancock collections, usually 

 coming from south of Panama rather than north, the lateral spines of 

 which are as long as the width of the five adjacent teeth. The writer 

 was unable to locate the Rathbun specimen at the National Museum 

 and has since learned that its misplacement was the result of a simple 

 switch with P. ordwayi at the time the specimens were removed from 

 their containers to be photographed. 



