S. I. Smith — Crustaceans of the Atlantic Coast. 
105 
a result of the difference in their habitats, the stenolepis being con- 
fined to shallow water where the bottom is overgrown with eel-grass 
or algae, abounding particularly among eel-grass during the summer 
and autumn ; while the mixta is apparently confined to deeper, and, 
at least in summer, very much colder, water, ranging from twenty to 
a hundred or more fathoms, where there is no eel-grass and seldom, 
if ever, algae. 
The stenolepis is an annual species ; the young appear in early 
summer, come to maturity early in the winter, produce young from 
mid-winter to spring, and all the mature individuals disappear before 
the second summer, the males disappearing long before the females. 
The following tabulation of t he results of an examination of several 
collections made at different seasons of the year, illustrates this fact. 
Locality. 
Date. 
No. of specimens, 
age and sex. 
Length 
in mm. 
Remarks. 
Vineyard Sd.. 
Julv 4 
1 0 + ; young. 
10 to 15 
Among eel-grass. 
Casco Bay, 
14 
50+ “ 
10 to 18 
U U 
it 
16 
100+ “ 
12 to 18 
44 
Aug. 19 
200+ “ 
15 to 18 
“ 
Halifax, 
25 
2 
14 
16 fathoms, algae. 
Casco Bay, 
27 
20 + 
15 to 20 
18 fathoms, rocks and sponges. 
Vineyard Sd., 
Sept. 2 
3 “ 
17 
Taken at surface. 
Halifax, 
6 
9 “ 
14 to 16 
16 fathoms, sand and algae. 
It 
15 
8 “ 
14 to 16 
18 fathoms, mud and sand. 
Vineyard Sd., 
3 Dec 13 
80; females. 
25 to 30 } 
Ovigerous sacs well developed 
16; males. 
21 to 24 j 
and many filled with eggs. 
U 
100 + ; females. 
24 to 28 [ 
Ovigerous sacs well developed 
1 ; male. 
21-5 J 
and nearly all filled with eggs. 
44 
April 3 
50 + ; all females. 
25 to 29 
All with fully developed young 
or empty ovigerous sacs. 
4 
24 
100 + ; 
25 to 30 
Mostly with empty ovigerous 
sacs. 
May 12 
100 + ; 
25 to 29 
All, or very nearly all, with 
empty ovigerous sacs. 
Mysis oculata Kroyer ex 0. Fabricius. 
Mysis apinulosus Packard. Canadian Naturalist and Geologist, vol. viii, p. 419, 1 863. 
Mysis oculata Packard, Memoirs Boston Society Nat. Hist., vol. i, p. 301, 1867. 
Labrador!, “abundant along the whole coast” (Packard). Grin- 
ned Land, as far north as latitude 79° 29' (Miers). Greenland 
( Kroyer, Stimpson, et al.). Iceland (G. O. Sars). Buchholz and 
Miers each include Spitzbergen among the habitats of this species. 
The very closely allied form, M. relicta Lovcn, by Professor G. (). 
Sars regarded as only a variety M. oculata , occurs in the Gulf of 
Bothnia fG. O. Sars), in the fresh-water lakes of southern Scandina- 
via ! (Lovcn, G. ( ). Sars), and in Lakes Michigan! and Superior!. 
Trans. Conn. Acad., Vol. V. 14 April, 1879. 
