192 
BULLETIN OF THE BUREAU OF FISHERIES 
This species is represented by numerous specimens ranging in length from 22 to 115 millimeters 
(Jds to inches). The young of less than 30 millimeters do not show the lacinated scales dis- 
tinctly, although indications of projections on the margins of the scales may be detected under 
magnification. The young of this species and those of the genus Menidia, unlike the adults, can 
not be separated readily by the character of the scales. The present species, however, differs from 
Menidia menidia in having fewer anal rays, a character that is available in separating the young. 
This character, unfortunately, can not be used in M. beryllina, as the fin rays in that species are 
about the same in number as in M. vagrans. In these species, however, the position of the dorsal 
fin with reference to the anal, is helpful, for in M. beryllina the first dorsal is wholly in advance of 
the anal and the origin of the second dorsal is over about the middle of the anal. In M. vagrans 
the origin of the first dorsal is over the origin of the anal and that of the second dorsal is behind the 
middle of base of anal. 
Two species of Membras have been described from the United States. One of these, M. 
vagrans, was supposed to represent the Gulf coast form and the other, M. laciniatus, the Atlantic 
coast form, and they were supposed to differ in the number of soft rays in the anal fin and in the 
number of scales in a lateral series. The Chesapeake Bay fish, according to the range assigned, 
therefore should be M. laciniata. In 119 specimens examined the number of anal rays varies from 
17 to 22, 2 of this number having 17 rays, 15 having 18 rays, 30 having 19 rays, 48 having 20 rays, 
19 having 21 rays, and 5 having 22 rays. The number of scales in a lateral series, in 38 specimens, 
varies from 42 to 50, as follows: Four specimens with 42 scales, 3 with 43, 5 with 44, 6 with 45, 4 
with 46, 6 with 47, 8 with 48, 1 with 49, and 1 with 50. This range covers the extremes of both 
forms, as given in current works. The extremes are not covered with respect to the number of anal 
rays, since specimens from the Gulf coast with as few as 14 rays have been recorded; a pronounced 
intergradation nevertheless is evident. Smith (1907, p. 178) referred laciniata to the synonomy 
of vagrans. Jordan and Hubbs (1919, p. 57) show that Atlantic and Gulf specimens intergrade, 
but they retain the names, regarding them as representing subspecies. The data presented herein 
appear to show that the retention of the names as representing subspecies is scarcely tenable. 
The food of this silverside, according to 13 stomachs taken from fish collected at various times 
and places, consists mainly of small crustaceans, and among them copepods constituted the main 
bulk of the material eaten. Other foods found consisted of fragments of insects and small ova of 
unknown origin. A few films of algae also were found. 
The spawning period in this species appears to be a protracted one, as specimens with well 
distended sexual organs, captured from May to August, occur in the collection. It seems probable 
that this silverside, like Menidia menidia, spawns among vegetation, to which the eggs become 
attached. 
This fish reaches a maximum length in Chesapeake Bay of about 43^ inches. It is common in 
the southern part of the bay but rather rare in the northern sections. No specimens were secured 
during the winter months. It runs up streams to brackish water, being somewhat more salt-water 
in its habits, however, than Menidia menidia. The species is of no direct commercial importance; 
its main value is as food for larger predatory food fishes. 
Habitat. — New York to Tampico, Mexico, if M. vagrans and M. laciniata are regarded as 
identical. 
Chesapeake localities. — (a) Previous record: Cape Charles city, (b) Specimens in collection: 
From numerous localities from Havre de Grace, Md., to Cape Charles and Norfolk, Va.; common 
toward the mouth of the bay. 
Family XLVI.— MUGILIDjE. The mullets 
Body elongate, somewhat compressed; mouth rather small, the jaws with small teeth or none; 
premaxillaries protractile; gills 4, a slit behind the fourth; branchiostegals 5 or 6; scales large, 
cycloid; no lateral line, the scales, however, with furrows forming lateral streaks; air bladder large; 
intestinal canal long; two short dorsal fins, well separated, the anterior one with four stiff spines; 
caudal fin forked; anal fin with two or three graduated spines; ventral fins abdominal with I, 5 
rays. A single genus of this family of fresh-water and marine fishes, inhabiting the warmer regions 
of the world, occurs in Chesapeake Bay. 
