part 1 garth: pacific oxyrhyncha 313 



H. pubescens there protrudes only a triangular spine, directed posteriorly 

 instead of dorsally. The rostrum of H. pyriformis is more elongate, the 

 length of each horn exceeding its basal width, although not the width of 

 the two combined. The granules of the lateral margin are four in num- 

 ber, but of the many in H. pubescens it is the same four, one hepatic and 

 three branchial, which show greatest development. More important 

 differences may be noted in the double crest of spines on the manus of 

 H. pyriformis which extends the length of the superior border, and the 

 hirsute palm, that of H. pubescens being entirely smooth and bare. The 

 greater pubescence of H. pyriformis is particularly noticeable ventrally, 

 where it extends to the sternum and abdomen, which in H. pubescens 

 are almost bare. The male first pleopods are remarkably alike. A similar 

 resemblance exists between H. camptacantha of the Gulf of California 

 and H. edwardsi, also of the Galapagos Islands. There can be little doubt 

 but that each Galapagos species has been derived from the corresponding 

 mainland species, and that but comparatively recently. 



Herbstia tumida (Stimpson) 

 Plate R, Figs. 1-5; Plate S, Figs. 3, 4, 6 ; Plate 34, Fig. 4 



Herbstiella tumida Stimpson, 1871a, p. 95. 



Herbstia tumida, A. Milne Edwards, 1875, p. 79. Rathbun, 1925, p. 299, 

 pi. 105, figs. 5, 6. Finnegan, 1931, p. 623. Crane, 1947, p. 72. 

 Garth, 1948, p. 27. 

 Herbstia (Herbstiella) tumida, Miers, 1886, p. 49. 

 ? Herbstia tumida, Crane, 1937, p. 59. 



Type: Female holotype, length ca. 12.7 mm, originally in the col- 

 lections of the Smithsonian Institution, no longer extant. 



Type locality: Manzanillo, Mexico; John Xantus, collector. 



Localities subsequently reported, with collectors: Gulf of California, 

 Mexico: American Museum of Natural History (Rathbun) ; Arena 

 Bank, 2.5 fathoms, Zaca (Crane, 1937). Panama: Bahia Honda, Zaca 

 (Crane, 1947) ; Isla Saboga, Perlas Islands, 4 meters, and Guayabo 

 Chiquito, 8-10 meters, Askoy (Garth). Colombia: Gorgona Island, St. 

 George (Finnegan) ; same locality, 4-6.5 meters, Askoy (Garth). 



Atlantic analogue: Herbstia depressa Stimpson. 



Diagnosis: Basal antennal article short and broad, only two outer 

 marginal teeth, including the anteroexternal. First movable article of 

 antenna reaching or exceeding tip of rostrum; anteroexternal spine di- 



