92 " THETIS " SCIENTIFIC RESULTS. 



The gill opening is slightly oblique, placed under tlie centre of 

 the eye and directed to its posterior margin ; it is shorter than 

 the eye and is separated therefrom by less than its own length. 

 Nostrils approximate, each with a skinny margin, placed in front 

 of the upper anterior angle of the eye. 



The teeth are damaged. There are three pairs in the lower 

 jaw. 



Upper profile of head straight. From the spine to the rays the 

 body is also sti-aight and ascends very slightly, the first ray mark- 

 ing the highest point of the body, whence it descends in an even 

 curve to the caudal pedicel. When the ventral process is 

 depressed the lower profile is an even low arc, broken by an 

 obtuse angle when the process is extended. 



The dorsal spine is placed over the posterior third of the eye ; 

 it is slightly curved backward at the base, otherwise straight, 1-3 

 in the length of the head, strong at the base, much weaker above ; 

 the front is rounded and without enlarged spines, excepting a few 

 small ones at the apex ; it is closely studded with low uniform 

 spinules, as determined with a hand lens, all trending upwards. 

 At each lateral margin is a row of low conical spines directed 

 outward and downwards. The dorsal and anal rays are similar, 

 of medium height ; the latter commences under the sixth dorsal 

 ray and terminates slightly behind that fin. The ventral spine is 

 below the space between the dorsal spine and rays, when extended 

 rather nearer the former, when depressed rather nearer the latter ; 

 it is fixed and has eight prominent spines, one pair directed 

 forwards, two sideways, and four backwai'ds; of the latter one 

 pair is placed above the other. The pectoral fin is one half longer 

 than the eye, beneath the centre of which its base is inserted. 

 Caudal long and rounded, no short external rays, the pedicel com- 

 pressed, without either spines or bristles ; its height equals the 

 diameter of the eye. 



Skin verj' rough, its texture resembling that of a wire flesh- 

 brush ; scales distinct ; with from one to four slender curved spines 

 . measuring 1 •? mm. in length arising from a bulbous eminence. 



Colour. — In spirits uniform greenish-yellow, fins yellow without 

 markings. 



It is with some reluctance that I name a MonacatUhus^ 

 especially as many of our species are ill-described. On tlie 

 whole it seems to be wiser to adopt this course, to supply an 

 ade({uate description and reliable figure. If more species were 

 figured we should have less synonomy, for, as Dr. P. P. Carpenter 

 said, with the best desire for accuracy and the greatest care, it is 

 hardly possible for an authui' to so describe tliat his readers shall 

 see specimens as he sees them. 



