70 
yond the anterior margin of the anal. Insertion of 
ventrals under the anterior margin of first dorsal, and 
behind the pectorals. 
Cottus Alvordii, Grd.—Body stout and 
short, tapering rapidly away. A second preopercular 
spine, very minute. Origin of anal fin opposite the 
third ray of second dorsal. Tip of pectorals extend- 
ing beyond the anterior margin of the second dorsal 
and anal fins. Insertion of ventrals near the lower 
edge of pectorals, in advance of the anterior dorsal. 
Cottus meridionalis, Grd.—Body stout 
and short. A second and third, very minute 
spines on the preopercular. Origin of anal fin op- 
posite to fourth ray of second dorsal. Tip of pecto- 
rals not reaching the anal. Insertion of ventrals 
even with the lower edge of the pectorals, in advance 
of the anterior dorsal. 
II. Rays of ventral fins, four in number. 
Cottus gracilis, Heck.—Body fusiform. 
Tip of pectoral fins extending beyond the fourth 
ray of second dorsal, and first of anal fin. Occa- 
sional palatine teeth. Insertion of ventrals under 
the pectorals, and in advance of anterior dorsal. 
Cottus viscosus, Hald—Body subcylindri- 
cal, stout. Tip of pectorals not reaching the anterior 
margin of the anal. Insertion of yentrals behind 
the pectorals, and in advance of the anterior dorsal. 
Cottus Franklinii, Agass.—Body nearly 
cylindrical. Tip of pectoral fins not reaching the 
anterior margin of second dorsal. Insertion of ven- 
trals in advance of the anterior dorsal, and under 
the middle of pectorals. 
Cottus gobioides, Grd.—Body subcylin- 
drical. Tip of pectoral fins not reaching the anal. 
Insertion of ventrals under the upper edge of the 
pectorals. 
Cottus boleoides, Grd.—Body fusiform, 
slender. Tip of pectoral fins extending beyond the 
fifth ray of second dorsal, and third of anal, fins. 
MONOGRAPH OF THE FRESH WATER 
III. 
bus pinnarum pectoralium ultra anteriorem pinne 
analis marginem prolatis. Pinnis ventralibus sub 
anteriorem marginem pinnze dorsalis prime et post 
pectorales, insertis. 
Cottus Alvordii, Grd.—Corpore crasso 
brevique citd decrescente. Altera spina przeopercu- 
lari, admodum parva. Origine pinne analis posita 
ex adverso tertio pinnz dorsalis secunde radio. 
Extremitatibus pinnarum pectoralium ultra anterio- 
rem pinnarum dorsalis secundz et analis marginem 
porrectis. Pinnis ventralibus prope inferiorem pec- 
toralium marginem et ante dorsalem anteriorem, in- 
sertis. 
Cottus meridionalis, Grd. — Corpore 
crasso brevique. Spina minima secunda atque ter- 
tia supra preeopercularem. Origine pinnz analis 
ex adverso quarto dorsalis secundze radio. Extremi- 
tatibus pinnarum pectoralium non porrectis ad pin- 
nam analem. Pinnis ventralibus in eadem linea 
qua pectorales, et ante dorsalem anteriorem, insertis. 
IJ. Pinnarum pectoralium radiis, quatuor. 
Cottus gracilis, Heck.—Corpore fusiforme. 
Extremitatibus pinnarum pectoralium ultra quartum 
pinne dorsalis secundz et primum analis radium 
porrectis. Dentibus palatinis aliquando occurentibus. 
Pinnis ventralibus sub pectorales et ante dorsalem 
anteriorem, insertis. 
Cottus viscosus, Hald.—Corpore subcylin- 
drico, crasso. Extremitatibus pinnarum pectoralium 
non porrectis ad anteriorem pinnze analis marginem. 
Pinnis ventralibus post pectorales et ante dorsalem 
anteriorem, insertis. 
Cottus Franklinii, Agass.—Corpore cy- 
lindrico. Extremitatibus pinnarum pectoralium non 
productis ad anteriorem pinnze dorsalis secundze mar- 
ginem. Pinnis ventralibus ante dorsalem anteriorem 
et sub pectoralium medio, insertis. 
Cottus gobioides, Grd.—Corpore subcylin- 
drico. Extremitatibus pinnarum pectoralium non 
productis ad pinnam analem. Pinnis ventralibus 
sub superiorem pectoralium marginem, insertis. 
Cottus boleoides, Grd.—Corpore fusiforme, 
gracile. Extremitatibus pinnarum pectoralium ultra 
quintum pinnz dorsalis secundz, et tertium analis 
