246 Mr. J. Y. Jolinson on rare and Uttle-Jcnown 



of the genuSj that there are no teeth on the palate. In both of 

 my specimens there was a small patch of minute teeth on each 

 palatine bone. 



The " thumb-mark " on the sides of both specimens was nearly 

 obsolete. The colour was a lilac-grey, deeper on the back, with 

 an iridescent lustre in various parts. 



Cytttis {Zeus) rosens, Lowe, sp. 



The geniis Cyttus was established by Dr. Giinther, in his 

 * Catalogue of Pishes in the Collection of the British Museum ' 

 (ii. p. 396) for the reception of fishes which are distinguishable 

 from those falling into the genus Zeus by the want of bony plates 

 along the base of the dorsal and anal fins, and by the spines of 

 the latter fin being limited to two. The present species had 

 been briefly defined by Mr. Lowe as a member of the genus Zeus 

 in the Proc. Zool. Soc. 1843, p. 85. Two examples having lately 

 occurred, taken in the months of Pebruary and March, I proceed 

 to give a fuller description of this very rare fish. 



D. 7 or 8 + 28 or 29. A. lor 2 + 29. P.M. V. 9. B.M. 7. 

 C. IV. 5 + 6. IV. 



The Dory-like body is compressed, elevated, and coloured a 

 pinky red, without maculse, the sides, in certain lights, being 

 silvery, washed with red. Very small scales are imbedded in a 

 smooth shining skin, those of the lateral line being about 75 in 

 number. Between the throat and the vent there is a series of 

 five (Dr. Giinther says three) oval bony plates, each marked with 

 radiating striae, and having a median crest which becomes on 

 some of them a short spine directed backwards. In one speci- 

 men the third plate is the longest, in the other the fourth. 



The height of the body is to the total length, the mouth being 

 closed, as 1 to 2^. The head, when the mouth is closed, is to 

 the total length as 1 to 3f , and is therefore less than the height. 

 The thickness of the body behind the pectoral fins compared 

 with the greatest height varied in the two specimens from 1 to 5 

 to 1 to 3|, the larger being proportionally much thicker. The 

 vertex is covered with a smooth, transparent, scaleless skin. 

 Behind the eyes the sides of the head are striate, and at the 

 nape there is a broad transverse depression. The large eye is 

 round, or slightly oval, with a diameter which is contained iu 

 the length of the head, the mouth being closed, about 2~ times. 

 It is placed high up, and takes part in the profile. The border 

 of the frontal bone above it is toothed. The distance from eye 

 to eye is about equal to the diameter. The openings into each 

 pituitary sac are close together, above the anterior margin of the 

 eye. The outer and posterior one is large, and obliquely oval. 



