Euphyllopoda Q 17 



3 males and 4 females from a small freshwater lake, and in a stream 



under the ice at Discovery bay, east side of Ellesmere island (Lat. 81° 41' N., 



Long. 64° 45' W.), Hart, Esq., coll. (Miers, 1877, p. 105). 



t 



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, Kjolen and the 

 Dovre mountains, etc., in Scandinavia (Sars, 1896, Lundblad, 1914-15); Kol- 

 gujew island (Zykoff, 1905); Novaja ZemUa (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 D6es, 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 Dees, 

 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 Kjolen 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 circumpolar distribution and indicate its southern 

 limit on the lowlands. 



Field Notes 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), IJ mm. long. It quite corresponds with the 

 "metanauplius" described by Sars (1896, p. 53, Tab. VIII, fig. 15). 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 metanaupUi (stage III) from 1| 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. 



2 Abdomen cleft at tip, eacli part ending in a spine, but no cercopods to be seen yet. 



26549—2 



