138 TL'AVELS AMONGST THE GREAT ANDES. 



thiui in the upper ; the outer row being y-shaped, while the two or three 

 iiinei' I'ows are siniihxr in form but much smaller. Fins — the dorsal is situ- 

 ated in the anterior half of the total length, excluding the caudal fin, its first 

 I'ay § the length of the head is semi-osseous in its lower portion, while its 

 anterior and lateral surfaces are covered with fine spines directed upwards, — 

 its remaining rays ai'e liranched. There is no distinct second dorsal in the 

 larger examples, but in the two smaller ones there is a constriction along the 

 body as if an adi2)ose fin had extended from the first dorsal to the caudal but 

 which becomes lost in the larger specimens. Caudal — emarginate, with the 

 outer rays spinate as in the first dorsal ray, but to a less extent. Pectoral 

 commences under the gill-opening, its outer ray very similar to the first of 

 the dorsal, Init stronger and ^ longer, and extending to above the ventral. 



CYCLOPIUM CYCLOPUM, HUMBOLDT. 



A. HEAD, FRONT VIEW. B. VENTRAL FIN. 



The \cntral inserted on a line lieneath the third or fourth dorsal ray. It is 

 rather longer than the pectoral, while its outer ray is of a similar character. 

 It does not exten<l to so far as the anal, which latter has the first ray similar 

 to those of the other fins but shorter. Skin rugose, and covered with small, 

 poi'ous orifices. Lateral-line distinct, consisting of small circular orifices, and 

 in the last half of the body of small tubes. Colour, now of a leaden hue, 

 having a yellowish tinge beneath. 



Four specimens were received from Eiobani1)a. 



Length of specimen 2 •2 inches; of head 4f of caiulal fin 7 in the total length. 



2-1 ,, ,, 4^ ,, 7 



1-9 ,, „ 4| „ 61 ,, 



!■« ,, ,, H „ 6 



This form dift'ers from the i)receding one in being 2)r()])()rtioilately a 

 little more elongated and Ijeing moi'e or less covered with black markings. 

 The largest has no distinct adipose dorsal, but the same indistinct appearance 

 as observed in some of the other fishes ; the one second in size (2"1 inches) 

 has this indistinct adipose fin with a small spine at its posterior termination 



