5. MONACANXntJS. 235 



Brachaluteres trossulus, Bleek. Ned. Ti/ds. Dierk. iii. 1866, p. 13 

 (name only). 



D. (25) 28. A. (23) 26. 



Skin densely covered with slender, flexible, acute bristles, which 

 are so delicate as to give a velvety feel to the finger. Body elevated ; 

 the height from the second dorsal fin (the commencement of which 

 is the most elevated part of tue dorsal profile) to the point of the 

 pelvic bone is equal to the total leng-th (without caudal). Snout 

 obtuse, with the upper profile nearly straight. The dorsal spine 

 stands over the middle of the orbit, and is roundish, much shorter 

 than the head, and densely covered with minute grains, which 

 lengthen into very fine acicular bristles. No ventral spine. Dorsal 

 and anal fins low. Blackish green, with some minute darker specks 

 and dots of a pale colour scattered over the body, and most crowded 

 on the face and flanks. Along the pehic bono and near the ab- 

 domen the dots ruu into streaks. (Micluirds.) 



Western Australia. 



The typical specimen (2| inches long) does not appear to have 

 been transferred to the British-Museum Collection, and is probably 

 lost. 



8. Monacanthus oculatus. 

 D. 24. A. 22. 



Skin densely covered with minute bristles, producing a velvety 

 appearance. Outline of the body subcircular, its depth being con- 

 tained once and one-third in the total length (without caudal). No 

 pelvic protuberance. Snout very obtuse, not projecting. The 

 dorsal spine is rather stout but short, placed behind the eye, and 

 ibout as long as the orbit ; it has no barbs. Dorsal and anal fins 

 )f moderate depth. Olive-coloured (in spirits), with about nine 

 rather irregular longitudinal rows of purplish ocelli edged with 

 white, and about as large as the pupil of the eye. 



South Australia. 



a. One and a half inch long. Port Lincoln. From the collection 

 of the Zoological Society. 



Aleuterius (?) baueri, E-ichards. Yoy. Ereb. & Terr. Fish. p. 68, is 

 very closely allied to the above species, but, unfortunately, known 

 from a drawing only. It is bright grass-green, with seven inter- 

 rupted dark brown longitudinal stripes ; nine short bars radiate 

 from the orbit. The artist has represented a dentition similar to 

 that of Diodon, but with notches on the edges of the jaws. Also the 

 single teeth are not so well difi'erentiated in M. ocularis as in other 

 Monacanthes ; but then it remains uncertain whether this is not due 

 to the young age of the individual. I could distinguish four teeth 

 clearly in the upper jaw, but two only in the lower. 



