5. EHOMBUS. 409 



upper eye is complete, formed by the frontal, whilst the lower eye 

 lies in the temporal groove, unprotected by an infraorbital ring, of 

 which only a small rudiment (a prajorbital) exists. The occipital 

 crest is of moderate height, bearing the interneurals of the anterior 

 dorsal rays. All the bones forming the bottom of the temporal 

 groove are well developed and ossitied. The bones of the jaws are 

 equally developed on l)oth sides ; there is a broad hiatus between 

 the dentary and articulary of the mandible. The urohyal is very 

 large, fixed between the symphysis of the lateral hyoids and that of 

 the humeri ; it is horseshoe-shaped, receiving the gill-membrane 

 into its concavity. The pubic bones have a broad lengthened base 

 for the insertion of the ventral fins, and are fixed by a long stylifonn 

 process to the humeral bones. 



There are twelve abdominal and nineteen caudal vertebrae ; the 

 neui-al and haemal spines of the middle vertebrae are exceedingly long 

 and strong, the first hi«mal and interha?mal spine forming together 

 a sort of pelvic bone. The length of the first haemal spine equals 

 that of the fourteen anterior vertebrae. Two interneurals and inter- 

 haemals always correspond to one neural and haemal ; sometimes a 

 third interneui-al and interhacmal is intercalated. Parapophyses of 

 the abdominal vertebrae broad, ^vith feeble ribs and epii)lcurals. 



2. Rhombus maeoticus. 



Pleuronectes maeoticus, Pall. Zoof/r. I}os!<.-As. iii. p. 419. 



Rhombu.s stellosus, Benn. Proc. Zool. Soc. 1835, p. 92. 



? Khombus rhombitis, Rdthhc, Faun. Krym, p. 351. 



Rhombu.^ maeoticus, Xordm. in Demid. Voi/. Rms. Merid. Poiss.n. 534. 



pi. 28. fig. 1, pis. 29 & 30; Kessler in Bull Soc. Nat. 3Iosc. 1859, pt. ii. 



p. 441. 



D. 62-65. A. 46. 



The height of the body is contained once and two-fifths in the 

 totjil length (without caudal), the length of the head t^vice and two- 

 thii'ds. Scales rudimentary, not imbricate. Body with more or less 

 numerous, bony, conical tubercles, which are as large as the eye ; 

 those on the head and on the blind side are much smaller, numerous 

 between the orbits and behind the upper eye ; interorbital space fiat, 

 its width being equal to the vertical diameter of the orbit ; no scales 

 on the fins. Lateral line ^vith a semicircular cuitc above the pec- 

 toral. Lower jaw prominent ; the length of the maxillaiy is con- 

 tained twice and a tliird in that of the head. The lower eye is 

 slightly in advance of the upper. The dorsal fin terminates close by 

 the root of the caudal ; its longest rays are behind the middle of the 

 fin, as long as the pectoral, and half as long as the head, (nll-rakoi-s 

 rather widely set, not quite so long as the eye, lanceolate. Brownish ; 

 bodv and fins mottled with reddish-brown. 



Black Sea. 



a. Fine specimen. Erzeroum. From tlic Collection of the Zoological 

 Society. — Type of Eh. .'^tclJosii.'!, Benn. 



