ORECTOLOBUS ORNATUS. 49 



Orectolobus. 



Orectolobus Bonaparte, 1834, Icon. Fauna Ital., Pesci, fasc. 7. 

 Crossorhinus Muller & Henle, 1837, Sitzb. Akad. wiss. Berlin, p. 113. 



Body stout, depressed, cavity half or more of the total length; tail shorter, 

 slender, compressed. Head and snout flattened above, broad, blunt. Nostrils 

 at the end of the snout, connected with the mouth by a nasoral groove; anterior 

 nasal valve with a cirrus. Mouth transverse, nearly terminal, with labial folds 

 on both jaws around the angles. Teeth compressed, narrow, with or without 

 small lateral denticles. Eye small, orbit elongate. Spiracle moderate, behind 

 and below the eye. Gill openings narrow, third to fifth above the pectoral, 

 fourth and fifth close together. Dorsals above the space between the ventrals 

 and the anal. Anal small, close to the subcaudal. Caudals narrow, other 

 fins short and broad; a notch between the subcaudal and the terminal. The 

 largest species reach a length of eight feet or more. 



Transgeneial folds, like those of Chiloscyllium, are absent, but on some 

 perhaps all of the species there is a short longitudinal fold below the symphysis 

 of the lower jaws, similar to that noted on species of Hemiscyllium, suggesting 

 a distensible mouth aperture with elastic ligaments, as in some serpents. 



No orbital papilla 



dermal lobes simple ....... ornatus (page 49) 



dermal lobes bifid to trifid japonicus (page 50) 



One orbital papilla 



one dermal lobe at side of throat . . . tentaculatus (page 51) 



Two orbital papillae 



two dermal lobes at side of throat 



a few short lobes below the chin . . . maculatus (page 52) 



Orectolobus ornatus. 



Crossorhinus ornatus De Vis, 1883, Proc. Linn, soc N. S. W., 8, p. 289. 

 Orectolobus ornatus Regan, 1908, Proc. Zool. soc. London, p. 356, pi. 11, f. 2. 



Closely allied to 0. maculatus, but differing in that the nasal cirrus and the 

 dermal lobes are less developed and more simple. The lobes occupy similar 

 positions; that is, there are two above the upper Up, two at the angle of the 

 mouth and two at the side of the head, but they are not bifid or trifid at their 

 ends. Gill openings small, hindmost two closer together, three above the pecto- 

 rals. Mouth moderate; lower labial folds long, not crossing the symphysis. 



