258 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [552] 
The females differ but little from the males except in the usual sexual 
characters. The figure, (Plate ILI, fig. 12,) made from a small female 
specimen, does not properly represent the anterior margin of the cara- 
pax. 
In life the young females are semi-translucent, a spot on each ocular 
peduncle, the peduncles and inner flagella of the antennule, the 
antennal scale, the telson and caudal lamelle more or less blackish 
trom deposits of black pigment, while each segment of the abdomen is 
marked with a rudely stellate spot of black. 
Large males of this species were found in the autumn among eel- 
grass, at New Haven, Connecticut, and the young abundantly in the 
_Same situation in May. Young females were collected in abundance 
‘during June and July, among the eel-grass in the shallow bays and 
coves about Vineyard Sound, while adult females, with the marsupial 
pouches filled with young, were collected, at Wood’s Hole, in abun- 
dance, April 1, by Mr. V. N. Edwards. 
Mysis AMERICANA. Smith, sp. nov. (p. 396.) 
Anterior margin distinctly rostrated, but only slightly projecting ; 
evenly rounded, the inferior angle projecting into a sharp tooth. An- 
tennule, in the male, with the densely ciliated sexual appendage similar 
to that in M. vulgaris of Europe; the outer flagellum nearly as long as 
the body, the inner slightly shorter. Antennal scale about three-fourths 
as long as the carapax, about nine times as long as broad, tapering 
regularly from the base to avery long and acute tip; both margins 
ciliated. Appendages of the fourth segment of the abdomen in the 
male similar to those in JJ. vulgaris. The outer ramus is slender and 
naked, and its pair of terminal stylets are equal in length, slender, curved 
toward the tip, and the distal half armed with numerous short setz ; 
the ultimate segment of the ramus itself is little more than half as long as 
the stylets, the penultimate segment four or five times as long as the 
terminal. Inner lamella of the appendages of the sixth segment about 
as long as the telson, narrow, slightly broadened at the base, and taper- 
ing to a slender but obtuse point; outer lamella once and a half as long 
as the inner, and eight times as long as broad, slightly tapering, the ex 
tremity subtruncate. Telson triangular, broadened at base, the lateral 
margins slightly convex posteriorly, and armed with stout spines alter- 
nating with intervals of several smaller ones; the tip very narrow, 
truncate, armed with a stout spine each side, and two small ones filling 
the space between their bases.. Length 10 to 12™, 
This species was found, in April, at Beesley’s Point, New Jersey, in 
pools, upon salt-marshes, and at the same locality the stomachs of the 
spotted flounder were found filled with them. Professor D. C. Eaton 
found it in great abundance among sea-weeds, &c., just below low-water 
mark, at New Haven, Connecticut, May 5, 1873. It was also taken in 
the dredge, in 4 to 6 fathoms, at New Haven, Connecticut, and in 25 
