




We 3 
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4 females i from a small freshwater lake, and in a stream 
er the ice at Discovery bay, east side of Ellesmere island (Lat. 81° 41’ N., 
- 64° 45’ W.), Hart, Hsq., coll. (Miers, 1877, p. 105). 
— 
EXTRALIMITAL DISTRIBUTION 
In Greenland it has been recorded from a number of localities (see Stephen- 
sen, 1917) on the north and west coasts, from Polaris bay (about lat. 82° N.) in 
north to Frederikshaab (about lat. 62° 30’ N.) in south. It has not yet been 
_ found on the east coast of Greenland, nor on Iceland and Spitsbergen. It is 
otherwise known from Lapland and Kola peninsula, Finmark, Kjélen and the 
Dovre mountains, etc., in Scandinavia (Sars, 1896, Lundblad, 1914-15); Kol- 
‘gujew island (Zykoff, 1905); Novaja Zemlia (Lilljeborg, 1877); and in Arctic 
Siberia between longitude 100° and 150° E. (Sars, 1897; Fischer, 1851); Bering 
island (Lilljeborg, 1887), Awatscha bay (about lat. 60° N.), Kamchatka (Daday 
de Dées, 1910); and Pribilof islands, collected on both St. George and St. Paul 
islands from 1872 to 1916 (specimens in U.S.N.M.); and in lakes on Hohen 
Tatras (Carpathians) at an elevation of about 1,650 metres (Daday de Dées, 
1890; a male and a female (about 1} cm, long) are in Brit. Mus. Nat. Hist., 
London (Norman Collection). 
Its occurrence on the Dovre and Kjélen Mountains (at about 2,500 feet 
elevation) and Carpathians, and perhaps also at White Horse ! must be explained 
~ as glacial, “relict-forms” continuing their existence in lakes at an elevation of 
not less than about 2,000 feet: The other records (excepting the one from 
Montreal) prove its complete cireumpolar distribution and indicate its southern 
limit on the lowlands. 
Fietp NotTEes AND DESCRIPTION OF MATERIAL 
Murdoch’s specimens from the vicinity of Point Barrow measured from 1 
to 2 cm. (exclusive of the cercopods), and were thus all mature males and females, 
which one would expect judging from the month (July) in which they were . 
secured. 
The specimens from Collinson point, June 22, 1914, measure from one to 
six mm., and include one nauplius (or rather transition stage between the 
nauplius and metanauplius stage), 1; mm. long. It quite corresponds with the 
“metanauplius”’ described by Sars (1896, p. 53, Tab. VIII, fig. 145). It is thus ~ 
a little older than the nauplii (stage I) I secured on June 17, 1916, at Chantry ~ 
island (see p. 20). It is characterized by the lack of lateral eyes, by the foliaceous 
legs (half a dozen pairs) and tail (abdomen) being only little developed,? and by 
the enormous second pair of antennae, labrum and mandibular-palp, the principal 
locomotory-organs. We may suppose it to be about a week old (stage II). 
Then there were half a dozen metanauplii (stage III) from 14 to 2 mm. 
long, and corresponding to Sars’ fig. 16 on Tab. VIII, and described by him, 
p. 54. Lateral, composite eyes are now present, the foliaceous legs are better 
developed, showing 8-9 distinct pairs well developed anteriorly, and decreasing 
behind while the three last pairs can be seen in a rudimentary state under the 
cuticula. The tail (abdomen) is less clumsy, and more elongate than in the 
preceding stage, and ends in two small, three-jointed, hairy cercopods. The 
labrum is still very large, but the second pair of antennae and the mandibular- 
palp are not nearly so large in proportion to the rest of the body as in the pre- 
ceding stage. 
Various features of the youngest of the larvae show, however, that it is a 
little older than the one figured by Sars (1896), and thus represent a stage between 
his figs. 16 and 17, on Tab. VIII. Thus my specimen has the lateral, composite 
eyes better developed (set off); the second pair of antennae is not so long and 

1 Elevation 2,000 to 3,000 feet. this ; 
2 Abdomen cleft at tip, each part ending in a spine, but no cercopods to be seen yet. 
26549—2 
Ea aor, hema ing a lek co Mit Been aL AR ae Ieee el 3) coe a 
ui s cy ala ik FN a Py Sas ome) 
- Euphyllopoda beste W4 Pea ye C re yaad 
