FAMILY, XL-GLYPHIDODONTID^. 381 



SYNOPSIS OF SPECIES. 



1. Tetradrachmum marginatum, D. tt-T6. ^- TT-rj. ^- 1- 25-26, L. tr. 3/12. Bluish, witli a dark zone 

 from the front dorsal spines to the ventral fin : scales on head and body with a blue spot. Red Sea, East coast 

 of Africa, seas of India to the ]\falay Archipelago and beyond. 



2. Tetradrachmtan aruanum, D. f|, A. W. L. 1. 2.5-27, L. tr. 3/11. White, with three vertical black 

 bands. Red Sea, East coast of Africa, seas of India to Polynesia. 



1. Tetradrachmum marginatum, Plate LXXIX, fig. 7. 



Pomacentms marginatus, Riipp. Atl. Fische, p. 38, t. viii, f. 2. 



Bascyllus marginatus, Cuv. and Val. v, p. 439, pi. 133, f. 2 ; Lefebvre, Voy. Abyss, vi, p. 231 ; Guer. 

 Menev. Iconog. iii, pi. xix, f. 6 ; Steind. Verb, zool-bot, Gcs. Wien, 1861, p. 77 ; Giinther, Catal. iv, p. 14 ; 

 Klunz. Fische Roth. Meer. Verb. z. b. Ges. Wien, 1871, p. 520. 



Bascyllus xantlwzona, Bleeker, Banda, i, p. 247 ; Giinther, Catal. iv, p. 14. 



Pomacentre gros yeux, Lienard, Dix. Rapp. Soc. Hist. Nat. Maur. p. 34. 



Tetradrachmum aanthozona, Bleeker, Fish. Madagascar, p. 85. 



B. V, D. ^.^^3, P. 17, V. 1/5, A. ^'„, C. 17, L. 1. 25-26, L. tr. 3/12. 



Length of head 3? to 4, of caudal 3f to 4, height of body If in the total length. .E^es— diameter 

 2\ in length of head, 1/2 to 3/4 of a diameter from end of snout, and 1 apart. Body strongly compressed : the 

 profile, omitting the caudal, is nearly orbicular. Preorbital narrow, the suborbital ring and hind edge 

 of preopercle serrated. Fins — dorsal spines from the second to the last of about equal length : caudal slightly 

 emarginate. Colours — Bluish. A dark band passes from in front of and below the first two dorsal spines, 

 through the base of the pectoral to the ventral. Snout dark. Every scale on the head with bright blue spot 

 edged with black, also those on the chest and lower two-thirds of the body : a few on the U])per third of 

 the body likewise similarly spotted. Soft dorsal and caudal yellow : spinous dorsal, ventral, and anal black. 



A small specimen of this species was di-edged off the Andamans by Mr. Wood- Mason. The one figured 

 was given me for that purpose by Dr. Bleeker. 



Habitat. — Red Sea, east coast of Africa, Andamans, to the Malay Archipelago, China, and beyond. 



2. Tetradrachmum aruanum, Plate LXXX, fig. 6. 



Chcetodon arcuatus, Linn. Mus. Ad. Fried, t. xxxiii, fig. 8, and Syst. Nat. p. 1243 ; Shaw, Zool. iv, 

 pp. .341 and 348. 



Clmtodon aruanus, Bloch. iii, p. 62, t. cxcviii, f. 2 ; Bl. Schn. p. 220; Shaw, Zool. iv, p. 348. 



Chcetodon abu dafar, Porsk. p. 16. 



Lutjaniis aruanus, Lacep. iv, p. 720. 



Pomacentrus aruanus, Riipp. Atl. Fische, p. 39. 



Chcetodon araneus, Bennett, Pish. Ceylon, p. 17, pi. xvii. 



Bascyllus aruanus, Cuv. and Val. v, p. 434 ; Bennett, Life of Raffles, p. 688 ; Riipp. N. W. Fische, 

 p. 129; Bleeker, Banda, i, p. 246, iii, p. 108; Giinther, Catal. iv, p. 12; Kner, Novara Fische, p. 241 : Klunz. 

 Fische Roth. Meer. Verb. z. b. Ges. Wien, 1871, p. 519. 



Tetradrachmum arcuatum, Cantor, Catal. p. 241 ; Bleeker, Bintang. 1868, p. 4. 



B. V, D. \i:\i, P. 17, y. 1/5, A. ^^.^, C. 15, L. 1. 25-27, L. tr. 3/10-11, Ciec. pyl. 3, Vert. 12/14. 



Length of head 4, of pectoral 4, of caudal 4| to 5, height of body 2^ in the total length. Eyes — 

 diameter 2/5 of length of head, 1/2 a diameter from end of snout, and 1 apart. The maxilla reaches 

 to below the anterior fourth of the orbit. Preorbital, pre- and sub- opercles serrated. Shoulder-bone also 

 serrated. Jl^i7!s— third dorsal spine the longest, as is also the second of the anal. Colours — pearl-white, with 

 three vertical black bands, the anterior descending from the three first dorsal spines through the eye oyer the 

 snout to the under surface of the lower jaw : "the second from the sixth to the ninth dorsal spines to 

 the ventral fins, which are black : the third from the base of the soft dorsal to the anal : caudal dark, light 

 posteriorly. 



Hctliitat. — Eastern coast of Africa through the seas of India to Polynesia, &c. : it is numerous at the 

 Andamans, Nicobars and Burmah, but much rarer in Western than in Eastern India. 



Genus, 4 — Pomacentehs, (Lacep.) Cuv. 



Pristotis, Riipp. : Lepidozygus, Giinther. 



Branchiostegcds four or five : pseudohrancMce. Preopercle and usually infraorlltal ring serrated. Teeth 

 small, compressed : the crowns smooth or emarginated. Borsal with 12 or 13, ancd with 2 spines. Scales rather 

 large. Lateral-line ceases below the soft dorsal fin. Air-vessel present. Pyloric appendages few. 



Geegraphical distribution. — Tropical seas of both hemispheres. 



