

Euphyllopoda Se 
mora sp.) a number of Branchinecta paludosa feeding upon them, twenty-six 
of which were secured, including seventeen males. 
og The three smalles males (12 mm.) had shorter claspers and less developed 
genitalia than the the larger ones (14-16 mm.), in which the antennae sometimes 
reached a length of 4 mm. Of the females the five smallest ones (8-12 mm.) 
had small ovisacs without eggs, while the four others (14-15 mm.) had big ovisaes 
with ripe eggs. 
Spring came considerably earlier in 1916 than in 1915 at Bernard harbour, 
and this had an important influence on the first appearance of insects on the 
ground and in freshwater, as well as upon the fairy-shrimps; though it has 
already been emphasized (p. 22), that all the ponds in one definite locality do 
not melt at the same time or rate; and thus the average size of fairy-shrimps 
in one pond may be smaller or larger than that of those in another pond. It is 
therefore perhaps not so surprising, that though I looked for them both at the 
end of June and the beginning of July, 1915, I did not find any before the middle 
of the last month, when I secured 32 immature specimens in the brackish pond 
repeatedly referred to, on July 15. They measured from 6 to 9 mm., and half 
a dozen of them were males (claspers very small), the rest females, with short 
ovisac without any eggs. The youngest of them (5-6 mm.) might even be 
called metanauplii, still having the second pair of antennae large. They were 
either swimming around in their typical way with the aid of their foliaceous legs, 
letting themselves drift, with the ventral side upwards, in the wind-current 
near the surface, or ‘browsing’ in the mud bottom and algae in the pond. It 
will be seen from above, that at about this time the succeeding year the fairy- 
shrimps were considerably larger, even in the same pond. Other immature 
individuals of the same size were observed to be common in other, larger, ponds 
inland at Bernard harbour the same day (July 15, 1915). 
Four days later the fairy-shrimps in the same brackish pond had attained 
a length of 7-11 mm., and I kept eleven of them. Three of these were males 
(10-11 mm.) with small claspers, the rest females (7-10 mm.) with short ovisac 
without any eggs. L 
On August 4, 1915, I again examined the same brackish pond. It still con- 
tained a number of fairy-shrimps, now about 15 mm. long. I secured 30 of these 
which all proved to be mature females, except one young male of the same 
length. The latter had only short claspers (see text figure 47) and the genitalia 
little developed, thus considerably less advanced than the males from July 14, 
1916 (see above), not to speak of the males secured on August 10, 1915 (see p. 24). 
We may, therefore, suppose that the egg from which it came hatched unusually 
late, though its size does not indicate it. It seemed as if all the other male fairy- 
shrimps in the pond now (August 4) had died off; and even the females were 
found less in the water itself than along the margin of the pond, often washed up 
here, wriggling around in the mud; and when placed in the water they seemed 
very sluggish. The rap'd evaporation of the shallow part of the pond at this 
time of the year has probably “‘stranded” them on land; and from their (females) 
present development and habits I suppose it is about time for them to die out, 
in this pond at least, after having deposited their eggs, most of the males appar- 
ently having died already. Perhaps the brackish nature of the water in this 
pond has something to do with the fact that their life thus seems to be shorter 
than in other ponds (see below); I tried to keep some of them alive, but they 
died very soon after. Their brilliant colours have already been described for 
specimens secured at Martin point the preceding year (p. 19). These from 
Bernard harbour differed somewhat from the Alaskan specimens, having the 
dark purple colour only as the characteristic, broad, dorsal stripe. On the other , 
hand the main colour is more blue, particularly the outer half of the foliaceous 
legs and the top of the head, though not the tail (abdomen). The mouth parts 
including labrum were red-brown, and the part of the ovarium at the base of 
the ovisac red-purple; intestine yellow-green. The mature males from Bernard 
Rt a us, | 
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