14 MEMOIRS OF THE CARNEGIE MUSEUM. 



which is found on the Pacific slope south of the dry area of central South America. 

 Members of the genera Cheirodon and Odontostilbe are found in the Chagres and 

 Atrato rivers in Panama and Colombia. Megalamphodus ecuadorensis is known 

 from one specimen taken in western Ecuador. 



The highest altitude is reached by Grundidus, which swarms in the streams of 

 the plains of Bogota at an elevation of about 9,000 feet. Several species are 

 found in the San Francisco basin at a considerable elevation. The rest are, as 

 far as known, confined to the low lands. 



Phylum PISCES Artedi. 



Class TELEOSTOMI Bonaparte. 



SuPERORDER OSTARIOPHYSI Sagemehl. 



Order PLECTOSPONDYLI Cope. 



Suborder HETEROGNATHI Cope. 



Family CHARACIDiE Gill. 



Subfamily Cheirodontin^ Eigenmann. 

 Teeth well-developed, in a single series, arranged vertically in the premaxillary, 

 dentary, and usually the maxillary. Usually some of the teeth with one or more 

 notches or cusps symmetrically arranged on either side of the median cusp. Ventral 

 surface rounded or slightly compressed, without serrations; body scaled; a parietal 

 and a frontal fontanel; dorsal short, with eleven or fewer rays; gill-membranes 

 free from the isthmus and from each other; nares close together, separated by a 

 flap only; adipose fin usually present. 



Key to the Genera op the Cheirodontin^. 

 a. No adipose fin; mouth small; armature of cheeks very weak. Teeth coaic or triscupid in both jaws; lateral 

 line incomplete. 

 h. Predorsal area partly naked; tactile papillae normal; teeth all conic in a regular series. 



1. Grundulus Valenciennes. 

 66. Predorsal area entirely scaled; tactile papilte excessively developed; teeth mostly tricuspid or conical. 



2. Spintherobolus Eigenmann. 

 aa. Adipose fin well developed, except in No. 7, Phanagoniales, which see. 

 c. Teeth tricuspid or conic. 



d. Teeth few, very heavy, tricuspid, five or six in each dentary, of which the first is directed upward 

 and outward, the third laterad, the fourth and later ones upward, at nearly a right angle to the 



