Jordan and Evermann. — Fishes of A'orth America. 1025 



pattern of coloratiou olivaceous, with dark vertical bands alternatly 

 long and short. Size, largest of the darters, ajjproaching that of Aapro, 

 to which genus it is more nearly related than the other darters are. (A 

 diminutive of Perca. ) 



a. Body deep; the depth more than | the length; body with orange shades in life, rex, 1416. 

 aa. Body subterete, the depth not more than J the length; no orange shades in life. 



CAl'RODES, 1417. 



U16. PEKCIXA REX, Jordan & Evermann. 



Head 3| ; depth 4i;. D. XIV-15; A. II, 11; scales 11-83 to 85-19, 5 

 rows of small scales on cheek. Body elongate, little compressed, the 

 form more robust than in Perciita caprodes, the back more elevated ; head 

 stouter, the snout more acuminate, and the mouth a little larger than in 

 P. caprodes \ the head similarly formed. Opercles and nape closely 

 scaled ; breast naked ; gill membranes nearly separate ; pseudobranchiae 

 very small ; median scales on ventral line moderately enlarged. Fins 

 higher than in P. caprodes, the longest ray of the soft dorsal slightly 

 more than half head. Adult, in spirits, mottled green above, yellowish 

 below ; 4 dark cross blotches on back ; about 10 roundish dark blotches 

 on sides, these almost confluent into a band ; a small black spot at base 

 of caudal ; no trace in young or old of parallel cross bands on side of 

 back, the young with the back covered with zigzag markings, the sides 

 with 10 short, vertical, inky black blotches about as high as the eye ; 

 second dorsal and caudal in adult yellowish, with oblique cross stripes 

 of black spots ; first dorsal yellowish, mottled, with a median dusky 



not serrate. Foramen of hypercoracoid much larger than in Perca. Pelvic bones proportion, 

 ately shorter and broader than in Perca. Uest of skeleton essentially as in Pcrcfi; number of 

 vertebr*, 23 + 21 = 44. Lower pharyngeals triangular-elliptical, with large teeth. 



As compared with the other darteis, the skull of Percitia is much broader between the eyes; 

 the parietal bones are more strongly ridged, the sutures more distinct, the top of the cranium 

 beyond the eyes more depressed, and the supraoccipital crest more developed than in most of the 

 others. In all these respects Percina is intermediate between Perca on the one hand, and the 

 extreme forms, Ammocrypta and Microperca, on the other. 



Tlie other darters form two irregular lines, the one with depressed cranium, and slenderer 

 bones, culminating in Ammocrypta; the other having the cranium more convex transversely, the 

 bones firmer and smooth, and the vertebne fewer in number. This group seems to culminate 

 in Microperca. 



So far as the skeletons are concerned, wo seem to be justified in the following inferences: 



1. The Etheoslominie are near allies of the Percinse, and should not form a separate family. 



2. They are among themselves closely related, and the extreme forms are so connected by 

 intermediate forms that they might with no great violence to nature be regarded as forming a 

 single genus. 



3. The species nearest allied to the typical Percinee is Percitia caprodes. This is the largest in 

 size, and of the others in general those smallest in size are most aberrant in structure. 



4. Those species which have usually been grouped together on external characters agree in 

 general in regard to the skeleton. 



5. As most of the skeletal characters change by degrees, none of them is of much use in 

 defining genera. 



6. These skeletal characters apparently of most importance are in the structure of the mouth, 

 the breadth of the frontal region (Percinti), the number of vertebrie, and the outline of the 

 transverse section of the skull across the parictals, whether ^ — ^ as in Holcosoma, etc., or 0> *8 

 in Elheoxtoma. The prolongations of the frontals in Etheostoina jiabellare and in Hadropleiiis 

 phoxorephahfx and its shortness in Ellieoalonia r.onale seem to l)e purely specific charactere. The 

 development of the nearly obsolete supraoccipital crest, the distinctness of the sutures, and the 

 sculpture of the parietala are features which offer no basis for trenchant division, except, per- 

 liaps, as distinguishing Percina from all the others. 



7. As defined liy skeletal characters alone, we may distinguish Percina, EOtenstoma, Microperca. 

 and perhaps Dipleaion and Ammocrypta from the rest as a distinct genera. The other groups, if 

 retained, must be separated from these and from each other by other characters. — Jordan A- 

 Eigenmamt, Proc. V. S. Nat. Mus., ISSo, 71. 



F.N. A. 66 



