FISHES OF PENNSYLVANIA. 107 

Genus ACANTHARCHUS Git. 
119. Acantharchus pomotis (Bairp). 
The Mud Sunfish. 
The mud sunfish has an oblong and moderately elongate body, its greatest depth 
near the vent two-fifths of the total length without the caudal. The greatest thick- 
ness is a little less than one-half the depth. The caudal peduncle is short and deep, 
its least depth two-fifths of greatest depth of body. The head is moderately large, 
rather more than one-third of total length without the caudal, its width equal to the 
length of its postorbital part. The snout is very short and obtuse, its length about 
one-half that of the eye. The eye is placed high, its diameter contained three and 
two-thirds timesin the length of the head. Theinterorbital space is slightly convex, 
its width three-fourths the length of the eye. The mouth is large, the maxilla 
broadly expanded behind and reaching nearly to below the hind margin of the eye. 
A well developed supplemental maxillary bone two-thirds as long as the eye; six 
rows of scales on the cheeks. The operculum ends in two thin, flat points, between 
which there is a black spot about two-fifths as long as the eye; gill-rakers short and 
few; five developed on the first arch, the longest two-fifths as long as the eye. The 
spinous dorsal begins over the fifth scale of the lateral line; its base is as long as the 
head without the snout; the first spine is very short, one-half as long as the eye; the 
spines increase very gradually in length to the last, which is as long as the eye and 
snout combined; the soft dorsal base is two-thirds as long as that of the spinous dor- 
sal; its rays are longer than the spines, the longest (fourth to sixth) about one-half 
as long as the head ; the anal begins under eighteenth scale of the lateral line; the 
first spine one-half as long as the eye; the spines increase in length to the last, 
which is one-third as long as the head; the rays are long, the longest (fourth) equal 
to postorbital length of head; the ventral reaches to the vent; the pectoral reaches to 
below the fifteenth scale of the lateral line; the caudal is rounded, its middle rays 
five-sevenths as long as the head; the lateral line is complete and runs parallel to the 
dorsal outline. D. XII, 11; A. VII, 10; V.I1, 5; P. 14. Scales 6-43-12. In spirits the 
evlor is dark brown; two or three dusky stripes-on the sides below the lateral line; 
a dark shade around the nape extending backward behind the eye; two dark stripes 
across the cheeks and operculum; a dark opercular flap as described above; the fins 
unspotted. In life the fish is dark green. The example described, No. 17,844, 
United States National Museum, from New Jersey, is four and one-fifth inches long; 
it has more dorsal and anal spines than are usually present in this sunfish. 
Prof. Baird, who first described the above species, called it the bass 
sunfish, because of its resemblance in shape to some of the basses. The 
mud sunfish ranges from New York to North Carolina in sluggish 
streams near the coast. Prof. Baird found it not rare in Cedar Swamp 
creek, near Beesley’s Point, N. J., in 1854, and the writer obtained a 
single individual in Gravelly Run, not far from this locality, in 1887, 
associated with the pirate perch, striped mud minnow, barred killifish 
and young pickerel. 
This fish reaches a length of six inches. It prefers muddy water and 
may even lie embedded in mud. 
The colors of living specimens were described by Prof. Baird as fol- 
lows: “ Dark greenish olive, with three or four irregular longitudinal 
bands of dull greenish yellow, and occasionally cloudy spots of golden 
green. Sides of the head of this color, with three indistinct bands of 
dark olive. Iris purplish brown; cornea olive green. Fins quite uni- 
