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22 G Canadian Arctic Expedition, 1918-1918 
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These larvae from Chantry island were orange (the labrum “kid; 
above the mouth parts being most strongly coloured), with black eyes, da 
intestine (food-particles) and pale appendages. I kept them alive for about 
month (Rearing No. 120) and on June 20, three days after being collected, they 
were all in the metanauplius stage, and the smallest of them of the same size as 
the biggest ones (see above) collected on June 17. Three days later their average _ 
length was 5 mm.; and two weeks later they were from 4 to 9 mm. long; the 
largest one could now be identified as an immature female, with an ovisac 14 
mm. long. These observations show the rate of growth of the younger stages 
of this species, even in captivity, without food. They also show the unequal 
lengths of the larvae, according to their date of hatching, a point already 
emphasized under Lepidurus arcticus (p. 9). 
On this place it is interesting to record the hatching of one of the Branch- 
inecta paludosa eggs collected (female animals) in a lake-pond at Bernard 
harbour on August 10, 1915 (see p. 24). The eggs were kept in my laboratory 
tent until the following spring (1916), in bottle of water (Rearing No. 94). 
The water with the eggs was of course frozen solid for nine months (September 
to May inclusive); nevertheless when it thawed out in the beginning of June, 
1916, three of the eggs hatched and the nauplii emerged. Unfortunately I did 
not observe them until the middle of the same month, when the larvae were 
2 mm. long, and thus corresponding to those collected at the same time on 
Chantry island (see above). I consider it very probable that the hatching of 
these eggs took place one or two days before it happened that year in the ponds 
where the ice would not melt as quickly as in a bottle. The experiment shows 
definitely the hardiness of the eggs of this species, and that they form the means 
of hibernating and propagating. 
On June 20, 1916, I collected in the brackish pond at Bernard harbour six 
immature Branchinecta paludosa as representatives of the sizes found there 
that date. They measured from 3 to 9 mm. in length, two of them (7, 83 mm.) 
could be identified as males (claspers small), and two (8, 9 mm.) as females 
with short ovisac without any eggs. The same day I also secured in the shallow 
pond on the sandflats (see Plate V, in Part J. of this volume) a few immature 
individuals (5-10 mm. long), and ten older ones (9-14 mm.). The latter ones 
were present in great numbers and of my specimens four are males, with big 
claspers, and of a more pale orange colour than the females, and without the 
dark purple-violet colour streak dorsally (see p. 19); while the females had olive- 
green eggs in the ovisac. The main reason for the difference in size between the 
specimens (from the same date) from the brackish pond, and those from the 
shallow pond, probably is that the latter, owing to its position and character 
melts earlier in the summer than the brackish pond, and more completely. 
On July 6, 1916, the Branchinecta paludosa in this shallow pond had attained 
a size of around 15 mm. and fifteen of them were kept. Seven of these were 
mature males and had big claspers, etc., while the rest were females with many 
ripe eggs in the ovisac. 
Four days later I collected eighteen more specimens in the same brackish 
pond; they measured from 7 to 15 mm., and five were males, the rest females. 
Of the former one (7 mm.) had the second pair of antennae little developed (see 
text figure 4g), and no signs of external genitalia; another (13 mm.) both of these 
sexual characters better developed (as text figure 42); while the three other 
males (14-15 mm.) had the second pair of antennae and the genitalia fully 
developed. Of the females the eight smallest (9-12 mm.) had the second pair 
of antennae shorter than in the male of 7 mm. and a short ovisac without any 
eggs (see text figure 4h). The five other females (13-15 mm.) had the larger 
ues (2nd pair), and the ovisac well developed, the latter with ripe eggs 
inside. 
The water hole with brackish water near the beach west of Bernard harbour 
examined July 14, 1916, contained besides many bright red Copepods (Hury- 






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