594 MOLLUSCA. 
Hab. Lower Cautrornia: La Paz (coll. Dunker). 
N.W. Mexico: Mazatlan (coll. Dunker). 
S.W. Costa Rica: Punta Arenas, in the Gulf of Nicoya (Hoffmann, in Mus. Berol.). 
S. Panama: Panama, abundantly from half-tide nearly up to the high-water mark of 
neap tides, on rocks, and on the lower parts of the trunks and about the roots 
of trees which were growing from a stony bottom (C. B. Adams *); Bay of 
Panama, on rocky places at low water (Cuming °*). 
CotomBia: Tumaco (Hopke, in Mus. Berol.). 
Ecuabor: in the mouth of the river of Guayaquil (Fontaine). 
This species is probably peculiar to the mangrove-swamps of the West Coast. 
Nassa luteostoma. 
Buccinum luteostomum, Broderip & Sowerby, Zool. Journ. iv. p. 8376 (1828-29) '; Kiener, Iconogr. 
Buccinum, p. 110, t. 30. fig. 1°; Eydoux et Souleyet, Voyage de la Bonite, Zool. ii. p. 608, 
t. 41. figg. 6, 7 (living animal and operculum) * (copied in M. A. Gray’s Fig. Moll. Anim. 
i. t. 85a. fig. 5). 
Nassa luteostoma, Troschel, Archiv f. Naturg. 1852, p. 172, t. 6. fig. 5 (operculum) *; Carpenter, 
Catal. Mazatlan Shells, p. 404°; Report Moll. W. N. Am. p. 268°; Reeve, Conch. Icon. 
vili., Nassa, t. 10. fig. 63°; Morch, Malak. Blatt. vii. p. 90 (1860-61) °. 
Nassa xanthostoma*, J. H. Gray, in Zool. of Capt. Beechey’s Voyage, p. 27, t. 36. fig. 8 (1839) °; 
M. A. Gray, Fig. Moll. Anim. iv. pp. 17, 71°. 
Shell suboval, pointed above, with strong, knobbed, nodulose ribs, about 10 in the last whorls, and numerous 
spiral ridges, grey or mud-brown ; aperture comparatively small, outer and columellar margins thick, 
yellow, the former denticulated within, both united above by a thin callus which reaches halfway to 
the next upper suture ; channel bent backward, open. 
Long. 103-144, diam. 7-10 ; apert. 63-8 millim. 
Hab. Cattrornta: San Diego (Jewett); La Paz (Forrer, in Mus. Berol.). 
N.W. Mexico: Mazatlan, extremely abundant (Reigen). 
S.W. Mexico: Acapulco (Lesson 28). 
W. GuaTEMALA: Champerico, in company with Potamides validus (Champion) ; 
Esteros de Champerico (Stoll). 
N. Nicaragua: Realejos (Lesson ? 8). 
S.W. Costa Rica: Punta Arenas, in the Gulf of Nicoya on sandy ground near the 
beach (Grsted °, Hoffmann, in Mus. Berol.) ; Costa Rica, without nearer indication 
of locality (v. Seebach). 
S. Panama: Panama, on sand, usually not far below high-water mark, in places 
where water is running when the tide is low (C. B. Adams). 
Also on the coast of Peru (Zschudi). Some authors27 give Senegal as locality, but 
it has not been found on any part of the West Coast of Africa by any recent 
collector. ; 
* “ Xanthosioma” is only a philological correction for Jutcostoma, this latter being compounded of a Latin 
(luteus, yellow) and a Greek word. 
