Jordan and Evermann. — Fishes of North America. 1020 



with caducous plates. Vertebne 39 to 44,19 + 23 = 42 {H. aspro)] 

 18 + 22=40 (//. evides); 18 + 22 = 40 {H. scierus) ; 19 + 20 = 39 {R. phox- 

 ocephahis). Parietal region more or less depressed, not strongly convex 

 in cross section ; supraoccipltal crest usually present, but small. Pyloric 

 C(Bca 2 to 4. Coloration bright ; often brilliant; sides usually with dark 

 blotches. The most active and graceful of the darters and many of them 

 with most attractive coloration. This group exhibits large variation in 

 minor characters, some of its species approaching very close to those of 

 EtheostoiiKi, the dividing line between the two genera being somewhat arbi- 

 trary. It seems best not to regard the subdivisions of this group as 

 distinct genera, as the characters which separate them disappear by 

 degrees. (('u5p''f, strong ; Trrepov, &ii.) 



a. Mfdiau Hue of belly with a series of enlargeil cadmous ventral ])lates, wliich fall off at 

 certain intervals leaving a naked strip from breast to vent; preoperole strictly entire; 

 gill membranes usually separate, sometimes somevvbat connected across the isthmus; 

 ventral fins well separated, the interspace usually not less than the breadth of their 

 base. 

 Alvordius :* 

 h. Palatine teeth present; dorsal spines 11 to 15; ventral tins widely separated. 



c. Lower jaw as long as upper; snout very narrow and pointed, especially in the adult; 



space between nioirth and gill cleft about 73 length of head; cheeks and 0])ercle8 



scaly; lateral blotches small, quadrate; scales small. phoxocephahs, 1418. 



cc. Lower jaw shorter than upper; snout less pointed; distance from mouth to gill 



cleft about half head. 



(/. Suout longer than eye; head very large and long, 3J/^ in length, chiefly naked; 



scales verj' small, about 90; 80 pores; sides with oblong blotches. 



MACROCEPHAIUS, 1419. 



Group A (ventrals widely separated). 



Percina rex. Hadropterus scierus. loa vitrea. 



Percina caprodes. Cottogaster shumardi. Ammocrypta pellucida. 



Hadropterus aspro, Cottogaster copelandi. Ammocrypta pellucida clara. 



Hadropterus peltatus. Cottogaster gilberti. Boleosoma poriostemone. 



Hadroptirua ouachitiv. Cottogaster uranidea. Etheostoma swannanoa. 



Iladriiptiius macrocephalus. Boleosoma nigrum. Hypohomus aurantiacus. 



Hadrojiterus phoxocephalus. Boleosoma nigrum olnistedi. Hypohomus cymatota>uia. 



Hadropterus nigrofasciatus. Boleosoma camurum. Hypohomus sijuamatus. 



Hadropterus roanoka. Crystallaria asprella. 



Group B (ventrals well separated, not quite so much so as in A). 

 Hadropterus evides. TJlocentra histrio. Ulocentra stigma'a. 



Etheostoma variatum. Etheostoma elegans. Etheostoma thalassinum. 



Etheostoma zonale. Etheostoma blennius. Boleosoma longimanus. 



Group C (ventrals rather close together). 

 Psychromaster tuscumbia. Diplesion blennioides. Microperca pni'liaris. 



Etheostoma obeyense. Microperca punctulata. Etheostoma squamiceps. 



Ulocentra simotera. 



Group D (ventrals vei-y close together, almost touching). 

 Etheostoma flabellare. Etheostoma whipplii. Etheostoma ))ottsii. 



Etheostoma ciieruleuni. Etheostoma jessia". Copelandellus ijuiescens. 



Etheostoma le(iiduiri, EtlieustoMKi iiitilincatuni. Boleichtliys fusiformis. 



Etheostoma cragini. Etheostoma caMiurum. Boleichtliys lusiformis eos. 



Etheostoma australe. Etheostoma maculatum. 



In several of these cases, the assignment is almost arbitrary; thus: I[<ulroplerus nigrofasciatus 

 has the interspace narrower than in Hntlmpleriis axpro, and scarcely wider than in Hadropterus 

 erides. biplesivn hleiinwiiles and Pj/xchroiuaxler liiscumlua might be placed in B as properly as in C. 

 We conclude that while this character may prove useful in classiticalion, we are unable to use 

 it to separate a large group or genus, Percina, from the still larger and more heterogeneous group, 

 Etiteostoma. 



* Named for General Benjamin Alvord, U. S. Army, a gentleman interested in natural history, 

 who discovered "Almrdius maailatus,'' at Fort Gratiot on Lake Huron. 



