Shell up to 21.0 mm in length, elongate-ovate and occasionally inflated anteriorly to sutures in mature specimens, teleoconch of 7-8%4 convex whorls, protoconch of 2½-3 glassy embryonic whorls, last whorl finely carinate, sutures adpressed; sculptured with moderate to numerous axial riblets which number from 23-57 on the penultimate and from 20-52 on the body whorl; spiral sculpture consists of very fine spiral striae which are either confined to interspaces of axial ribs or override axials rendering these slightly nodulose; striae number from 8-10 on the penultimate and from 10-13 on the body whorl, followed by 6-10 nodulose cords and an additional 5-7 cords on the siphonal fasciole, sutural den- ticles distinct, occasional senile individuals with a few, low, broad varices. Aperture narrow, outer lip thick and broadly variced, interior of aperture with 6-10 denticles, columellar callus narrow and only slightly broadening anteriorly and with 7-13 small denticles, siphonal notch and anal canal distinct. White to orange-brown in colour, spire whorls with 1-2 brown bands anterior and posterior to sutures, body whorl usually with 3 brown bands, aperture white to pale orange-brown and sometimes with darker bands within. TYPE LOCALITY. Tubuai I, Austral I (concinnus and concentrica); San Christoval, Solomon Is (interlirata); Torres Str., N.Australia (crebrilineata); Djibouti, [Somali Republic], Red Sea (voluptabilis); none (smithii; rotundicostata); Philippines (cribaria); Kali Bioek and Kali Glagah, Boemaijoe, Java, Pliocene of Indonesia (pseudomundus). DISTRIBUTION. From the Red Sea and the Persian Gulf to Japan and the Tuamotu Archipelago. In clean and weedy coral sand, subtidal to a depth of 150 m. Type specimens. Three syntypes of N.concinnus (Powys), are in the British Museum (N.H.), Lon- don, No.197362, and the specimen measuring length 18.8 mm, width 9.2 mm, is here selected as the lectotype (pl.28, fig.2). The holotype of Nassa interlirata E.A.Smith, is in the same Institution, No.1876.1.10.28, length 6.4 mm. The following types are in the Merseyside County Museum, Liver- pool: five syntypes of Nassa concentrica Marrat, and the specimen measuring length 9.6 mm, width 5.3 mm, is here designated as the lectotype (pl.28, fig. 5); four syntypes of N.smithii Marrat, and the specimen measuring length 12.6 mm, width 6.0 mm, is here designated as the lectotype (pl. 28, fig.4); two syntypes of N.rotundicostata Marrat, and the specimen measuring length 12.0 mm, width 6.7 mm, is here designated as the lectotype (pl.28, fig.6); ten syntypes of N.cribraria Marrat, and the specimen measuring length 9.6 mm, width 5.6 mm, is here designated as the lectotype (pl. 28, fig.7). The holotype of N.crebrilineata Rousseau, length 18.0 mm, width 9.0 mm, is in the Museum Na- tional d'Histoire Naturelle, Paris. Syntypes of N. voluptabilis Jousseaume, are in the same Institu- tion, and the specimen measuring length 12.0 mm, width 6.2 mm, is here designated as the lectotype (pl.28,fig.3). Material examined. RED SEA: Eilat, Gulf of Aqaba (TAU); Djibouti, Somali Republic, Gulf of Aden (MNHNP); PERSIAN GULF: 13 km E.N.E. of Patrick Stewart I Bank, 69 m (ZMC); EAST AFRICA: Mozambique (USNM); N.Ile Pamanzi, Mayotte I, Comoros Is (MNHNP); MADAGASCAR: Tulear (SMOM); REUNION I: Lagon de la Saline,(coll. Martin); MAURITIUS: (AIM; ZMC; USNM; LACM; AMS); THAILAND: Koh Chik; Koh Chang, c.56 m (both ZMC); INDONESIA: Java, 8°30'S & 114°28'E, 70-150 m; Java, 8°26'S & 114°29'E, 70 m (both ZMC); Kalahabi Harbour, Alor I, N. of Timor; Kuta Beach, Bali (both coll. McCausland); PHILIPPINES: Mariqui, Mindanao (USNM); Matabungkay, S.S.W. of Manila (AMS); Dungaree Beach, Subic Bay (coll. Salisbury); CHINA: Straits of Taiwan, S.China Sea, c. 150 m (NSMT); Peitaho (LACM); RYUKYU IS: Okinawa I (USNM; LACM; SDMNH); Seragaki, Okinawa (coll. Deynzer); JAPAN: Osima, Osumi (USNM); MARIANAS IS: Guam (USNM); Apra Harbour, Guam I (coll. McCausland); Piti Pt., Guam 1, 11 m (coll.Deynzer); CAROLINE IS: Kapingamarangi (USNM); Ponape (LACM; SDMNH); MARSHALL IS: Kwajalein Atoll (USNM); Enewetak lagoon (coll.Johnson); PAPUA NEW GUINEA: Kuia I, Lusancay I, Trobriand Is; East Cape; Finschhafen (all AMS); AUSTRALIA: Western Australia: Dampier (coll.Hansen); Roebuck Bay, Broome; (both AMS); Northern Territory: Darwin (AMS); Queensland: Heron I (NMV); Daydream I, Whitsunday Passage (coll. Powell); Mornington I (coll.Marrow); Lizard I; Trinity Bay; Low Isles near Port Douglas; Buchan's Pt., N. of Cairns; off Undine reef; off Cape Upstart, 37 m; Green 1, off Cairns; Yarracutter reef, off Cardwell; Slasher's reef, N. of Townsville; Tryon I, Capricorn group; N.E. Herald Cay, Coral Sea; Northwest I (all AMS); Hope I (coll.Lee); off Port Douglas (coll. Ritter); South Molle I (coll. Worthy); SOLOMON IS: Tulagi I, Florida group (coll. Hallinan); Bonigi I, Guadalcanal, 11-21 m (coll.Dillworth); Ata (AMS); NEW HEBRIDES: Teuma Bay, Efate I, 47 m (coll.Eker); Vila, Efate I (coll. Lepage); LOYALTY IS: Lifu I (AIM); NEW CALEDONIA: (ZMC); Ovaco (AMS); FIJI IS: Lomalagi, S. Viti Levu (coll.Eker); W.of Rat Tail Passage, Suva reef (coll.Mar- row); Suva, S. Viti Levu (SDMNH); Nadi Bay, W. Viti Levu (AMS); Lakeba I, Moce I and Karoni I, all Lau group (AIM); Lami, S. Viti Levu (coll.McCausland); Ogea I, Lau group (coll.Northgrove); SAMOA IS: Apia Harbour, Upolu (coll.Powell); Pago Pago (USNM); Fagaitua Bay, Tutuila I (LACM); TONGA IS: Nuku'alofa (coll.Lamb); Pangai I; Nuku'alofa (LACM); Vavau I (coll.Northgrove); COOK IS: Rarotonga (AIM); AUSTRAL IS: Tubuai I (USNM: coll. Trondle); SOCIETY IS: Tahiti (coll.Powell); off Fare, Huahine I (LACM); Punaavia, Tahiti (AMS); S.coast of Moorea I (coll. WOC); TUAMOTU ARCHIPELAGO: (USNM); Anaa I (coll. Trondle). Fossil record. PLIOCENE: Noil Lioe, Timor, Indonesia (Tesch in Wanner 1915); Bandjar Andjar, Java, In- donesia (K.Martin 1882); Nakoshi sand, Okinawa, Ryukyu Is (MacNeil 1960); PLEISTOCENE: Grissee, Java, Indonesia (K.Martin 1895.) Tomlin (1940) correctly placed Marrat's four new species in the synonymy of N.concinnus. The typical form has numerous, slender axial riblets, and voluptabilis Jousseaume also belongs to the multiribbed form. The forms rotundicostata, cribraria and concentrica have fewer ribs, while smithii is intermediate between the few-ribbed and multi-ribbed forms. There are specimens of N.concinnus labelled "Oahu, Hawaii Is" in the Los Angeles County Museum of Natural History. The species has as yet not been reliably recorded from the Hawaiian Islands, and this record requires confirmation. The holotype of Nassa interlirata E.A.Smith, although badly worn, is just recognizable as a minute individual of Nassarius concinnus.