FISHES OF CHESAPEAKE BAY 
137 
the upper angle of gill opening and origin of dorsal; dorsal fin moderate, higher in adult males than 
in females, inserted nearly an eye’s diameter in advance of origin of anal; caudal fin straight or 
slightly rounded posteriorly; anal fin similar to dorsal, the rays proportionately longer in adult 
males than in females; ventral fins rather small, inserted about an eye’s diameter nearer the tip of 
snout than base of caudal; pectoral fins moderate, 1.3 to 1.8 in head. 
Color of female dark olive above, pale underneath; scales on sides with dusky punctulations 
and dark edged, those on anterior part of sides with bluish and silvery reflections; a dark vertebral 
streak present in advance of dorsal; dorsal, caudal, and pectorals more or less greenish or olivaceous; 
other fins colorless. General color of male similar to female but somewhat brighter, at least during 
the breeding season; the anterior rays of the dorsal black or sometimes with only a black spot at 
base, the black occasionally extending on the outer margin of the fin; anal fin also sometimes with 
a dark margin; anal and ventrals with more or less red during the breeding season. The color of 
the young is similar to that of the adult female, the markings differentiating the sexes appearing 
when the fish has reached a length of about 25 millimeters. 
Many specimens of this species were taken, ranging in length from 24 to 58 millimeters (1 to 
2i^ inches). This fish is recognized by its small size and plain greenish coloration, no bars or 
stripes being present. 
The only food present in 28 stomachs examined consisted of small crustaceans. However, 
the species no doubt also feeds on other small animal life. In the aquarium it readily takes finely 
chopped fish and beef. 
Ripe or nearly ripe fish were taken from early in April until near the end of July. It seems 
probable that the fish spawn more than once suring a season, as the gravid females taken during 
the early part of the saeason, in addition to the ripe eggs, contained another size of eggs easily 
visible with the unaided eye. This may also account for the long spawning season. The eggs, 
when mature, are about 1 millimeter in diameter, and the largest number found in one fish was 104. 
Sexual maturity appears to be attained very soon after the color differentiation between the sexes 
takes place, or when the fish are about 25 millimeters in length. The largest individual taken 
during the present investigation was 58 millimeters (2^ inches) long, and it appears to represent 
the maximum size attained by the species. The females reach a somewhat larger size than the 
males, the average difference in the length being about one-fourth inch. 
This fish is very abundant in all brackish waters of Chesapeake Bay, but was not taken in 
strictly fresh water. It is especially plentiful in coves, bays, ponds, creeks, and open flats, where 
vegetation is present. Its abundance is indicated by the following catches made with a 30-foot 
collecting seine: Love Point, Md., May 12, 1922, brackish creek, bottom mud and vegetation, 
7 hauls, 18,300 Lucania parva; Annapolis, Md., May 2, 1922, brackish pond, bottom mud, dense 
vegetation, 20 hauls, 14,600 Lucania parva. The fish travel in schools and are often found in 
association with Gambusia and Fundulus. 
Several investigators have mentioned this species as being of value for mosquito control, but 
this appears to have been based upon the nature of its habitat rather than upon direct investigations, 
and no definite information is available. 
This fish is too small to be of commercial importance, but, because of its abundance and wide 
distribution, it no doubt is an important food for larger fishes. 
Habitat . — As given by Smith (1907, p. 151) and others, Cape Cod to Key West. 
Chesapeake localities. — (a) Previous records: “Lower Potomac,” St. George Island, and Cape 
Charles City. (5) Specimens in collection: From shore waters of all parts of the bay from Love 
Point, Md., to Lynnhaven Roads, Va. 
46. Genus FUNDULUS Lecepede. Killifishes; Mummichogs 
Body elongate, posteriorly compressed, back little or not elevated; head rather broad, usually 
depressed; mouth terminal or the lower jaw slightly projecting; teeth usually villiform and in nar- 
row bands; dorsal and anal fins usually higher in males than in females; caudal fin with straight or 
rounded margin; the anal fin not modified; oviparous, the sexes differing in color and size, the 
females being the larger. Several species of this genus frequent salt and brackish water and others, 
not considered in this report, are confined to strictly fresh water. 
