1914.] NATURAL SCIENCES OF PHILADELPHIA, 271 



LORICARIID^. 

 PLECOSTOMINiE. 



STONEIELLA gen. nov. 

 Type Stoneiella leopardus sp. nov. 



Teeth fine, but little enlarged at ends, moderately small, not 

 numerous. Interopercle with erectile spines, and these on movable 

 plate. Body spinescent almost everywhere above, especially 

 anteriorly. Lower surface of head, lower sides of abdomen and 

 belly naked. Lateral edges, as well as upper surfaces of head, 

 finely spinescent. Temporal plate imperforate. Tail short, com- 

 pressed. Adipose fin present. Anal with five branched rays. 



This genus differs from the related genera, or those of the present 

 subfamily, in the naked or unarmed lower regions. In its dentition 

 it approaches Lithoxus Eigenmann. One species. 



(Named for Dr. Witmer Stone, in slight recognition of his con- 

 tributions to natural history'.) 

 stoneiella leopardus sp. nov. Fig. 17. 



Head 4; depth 5; D. I, 8; A. I, 5; P. I, 6; V. I, 5; spinescent 

 armature of 1. 1. with about 24 bucklers, indistinctly defined; head 

 width lyV in its length, with head measured from snout tip to hind 

 •end of occipital process; head depth at gill-opening about 2; snout 

 1*; eye 5; width of buccal disk 2|; interorbital 2|; dorsal spine 1; 

 anal spine If; pectoral spine 1|; ventral spine 1|; least depth of 

 caudal peduncle 3; upper caudal lobe about 1| (tip damaged). 



Body moderately long, well depressed, convex above, flattened 

 below, deepest at dorsal origin and widest at pectoral origins. Caudal 

 peduncle stout, becomes more compressed behind, and length about 

 I its depth. 



Head large, broad, convex above, flattened below, and upper profile 

 & little inclined and nearly straight. Snout depressed, surface 

 .generally convex, as seen from above rather 6longately triangular 

 with length about f greatest width at point opposite front of eyes. 

 Eye superior, close on upper profile, a little ellipsoid, placed about 

 last third in head length measured to hind occipital process, and 

 •edges without eyelid, free. Mouth inferiorly anterior, with broad 

 rounded disk. Upper jaw retractile, with a series of 8 slender hooked 

 compressed bifid teeth, each with tips of bifurcations worn in 

 appearance as if somewhat truncate, and inner branch larger. Man- 

 dible with a series of 12 similar teeth. Teeth medianly in both jaws 

 larger, and lateral ones smallest. Inner buccal folds broad. Lips 



