5 
Gasterosteus cuviert (GIRARD). 
This partly naked stickleback is the only Gasterosteus in the collection. 
By some authors it is classed as a variety or subspecies of the fully armoured 
G. bispinosus, but the reason is not apparent. Its characters are very uniform 
over a wide range, including Hudson Bay, and intermediate forms, linking it 
with the alleged parent species, are not met within this range. These are the 
essentials of a good species, and entitle it to full recognition as such. 
It was found tobe common. At stations 1, 3, 8, 10, 11, 12 and 13 collections 
were made. It does not seem to be limited to tidal pools, creeks, estuaries, and 
shore waters, but occurs at considerable distances from the coast, as for instance 
at station 10. 
The fish are, on the average, small, the largest being 54 mm. in length, or a 
little over half the greatest length of G. bispinosus in the Gulf of St. Lawrence 
-and Atlantic shore waters of Nova Scotia. The lateral scales are typically 
4-4, occasionally 4-5, rarely 5-5; nothing beyond this is seen. They are counted 
from behind the one under the first dorsal spine backwards. 
G. bispinosus does not appear in the collection; it is doubtful if it occurs 
in Hudson Bay at all. In the United States National Museum there is one 
small collection of Gasterosteus from Hudson Bay, but it consists entirely of 
cuviert; neither is any other found in the collection made there by Rev’d. W. G. 
Walton in 1919 and examined by the writer. 
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