PART 1 GARTH : PACIFIC OXYRHYNCH A 71 



(Bell, 1836, pi. 8, figs. 1-lc), or with their reproductions in Rathbun 

 (1925, pi. 274, figs. 1-4), particularly the figures of the male abdomen 

 and chela. It was because of these features that the Cape San Francisco 

 specimen, a male, rather than the Salango Island specimen, a female, was 

 selected for illustration. The female from Salango Island, however, has 

 been selected as the neotype on the advice of L. B. Holthuis, who pointed 

 out the advantage of having as neotype a specimen collected from the 

 type locality as restricted below. 



Equally mature and of comparable size are a male specimen from 

 Cape San Francisco, station 850-38 (Plate E, fig. 1; Plate 3, fig. 4), 

 and an Askoy Expedition male from Ardita Bay, Colombia (Garth, 

 1948, p. 23). Measurements of the walking legs given above, but not 

 included in the Askoy report, are in the required descending order of 

 length (2.3.1.4), although this character is subject to variation 

 depending on sex, asymmetry and regeneration of appendages. 



The absence of Collodes gibbosus from the Galapagos fauna and the 

 possible reasons therefore have already been discussed (Garth, 1946, 

 p. 375). Localities at which Cuming, who obtained the specimens on 

 which Bell's studies rest, is also known to have collected include La 

 Plata and Salango Islands in Ecuador, as well as several islands in the 

 Bay of Panama (Carpenter, 1857). Contemporaneous Cumingiana 

 (Merrill, 1926; St. John, 1940) contains enough references to his 

 laxity with respect to written records to justify the assumption of an 

 exchange of labels between Galapagan and mainland specimens in the 

 case of possibly eight out of ten species likewise attributed to the islands 

 but not since found there, if indeed the specimens had written labels to 

 begin with (Cf. Garth, 1946, p. 343). In short, the provenance of most 

 of Bell's west coast species is, and always was, that little known stretch 

 of South American coastline between Cape Mala, Panama, and Punta 

 Santa Elena, Ecuador, now designated as the Panama Bight. The 

 restriction of the type locality of C. gibbosus to Salango Island, Ecuador, 

 a particular locus within this larger territory, and the selection of the 

 Salango Island specimen as neotype, give pointed recognition to this fact. 



The male specimen collected by H. N. Lowe at Acapulco (U.S.N.M. 

 No. 73441) is believed by the writer, because of its lack of carapace 

 spines, to represent this species rather than Collodes granosus Stimpson, 

 as identified by Rathbun. Apart from this possible record, Collodes 

 gibbosus has not been taken north of Central America. C. granosus 

 Stimpson, on the other hand, occurs from the Gulf of California to 



