[27] FLOUNDERS AND SOLES. 251 
23. PHRYNORHOMBUS REGIUS. 
(THE Top-KNOT.) 
La Petite Limandeile, Duhamel, ‘‘ Traité sur la Pesche, iii, sect. 9, p. 270, pl. 6, f. 5.” 
Pleuronectes regius, ‘‘la Calimande royale” Bonnaterre, Encyclopédie Méthodique, 
1788 (after Duhamel). 
Pleuronectes calimanda Lacépéde, Hist. Nat. Bo ida. ., iv, 1803 (after Duhamel). 
Pleuronectes punctatus ‘‘ Fleming, Werner, Mem., ii, 241” (not of Bloch.) 
Tthombus unimaculatus Risso, Europe RMeridionate, 1i1, 252, f. 35, 1826 (Nice). 
Phrynorhombus unimaculatus Giinther, iv, 414, 1862 (Dalmatia; Plymouth). 
Scophthalmus unimaculatus Steindachner, Ichth. Bericht., vi, 1868, 49 (Barcelona). 
Zeugopterus unimaculatus Day, Fish. Great Britain, ii, 17, pl. xcix (Belfast). 
Rhombus wniocellatus Nardo, Prodr. Ichth. Adriat., 135, 1827. 
Habitat.— Coasts of Southern Europe, north to England. 
This small flounder reaches a length of 5 or 6 inches. Our speci- 
mens are from Venice. We adopt the earliest name, regius, for this 
species, as it seems to belong to this fish without doubt. 
Genus XIII.—ZEUGOPTERUS. 
Zeugopterus Gottsche, Wiegmann’s Archiv, 1835, 178 (hirtus). 
Scophthalmus Bonaparte, Catologo Metodico dei Pesci Europei, 1845, 49 (hirtus). 
(Not of Rafinesque.) 
Zeugopterus Steenstrup, Oefvers. Dansk. Vidensk. Selsk. Forhandl., 1865, 95-112. 
_ Type: Pleuronectes hirtus Abilgaard=Pleuronectes punctatus Bloch. 
This genus is distinguished from Pleuronectes both by the union of 
the ventral and anal fins, and by the perforation instead of emargina- 
tion of the septum of the gill-cavity. This latter character was first 
noticed by Professor Steenstrup, who used it to define his genus Zeu- 
gopterus, which is equivalent to Lepidorhombus, Zeugopterus, and Phryno- 
rhombus of the present paper. But one species is known, widely dif- 
fused in Northern Europe. 
ANALYSIS OF SPECIES OF ZEUGOPTERUS. 
a. Body ovate, covered with small but very rough shagreen-like scales; blind side 
smooth ; caudal peduncle very short, the last rays of dorsal and anal inserted on 
the left side of it almost meeting across the base of the caudal fin; none cf the dor- 
sal rays exserted ; lateral line indistinct; eyes large, separated by a very narrow, 
scaly ridge; snout very short; gill-rakers short, thickish; lips thick; maxillary 
half as long as head. Left ventral inserted at chin, fully confluent with anal; 
right ventral long. Brown, with round black spots, one behind the curve of the 
lateral line, and one behind this on the straight portion; one near upper edge of 
gill opening, and one above upper eye; an oblique band from lower eye to subop- 
ercle. Depth2 inlength; head3; D.93 to 99; A.70to 80. Vertebra 12+ 25 =37. 
PUNCTATUS, 24. 
24. ZEUGOPTERUS PUNCTATUS. 
(THE BLACK FLUKE.) 
Pleuronectes punctatus Bloch, Ausliindische Fische, iii, 31, tafel 189, 1787. Gmelin, 
Syst. Natura, p. 1235, 1788. Bloch & Schneider, Systema Ichth., 1801, p. 155 
Zeugopterus punctatus Collett, Norges Fiske, 1875, 139. Day, Fishes Great Britain, 
voi. ii, p. 18, plate 6. ¢ 
