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rocks near the edge of the water, one might expect to see it, and provided there are rocks or other solid objects for its attachment it should be found at moderate depths a great deal farther west.
The rough periwinkle, Littorina rudis, is a widely distributed species that is found in Britain. It lives along the shore near the limit of high tides and spends a great part of its time out of the water. In the Baltic its distribution is said to be restricted to regions where the salinity is 7 or over, but elsewhere it has been found where the salinity is only 5-6 (e.g., in Randers Fiord). In face of these facts it is difficult to believe that the distribution of this species in Hamilton Inlet is limited by a salinity of 15, and further investigation may be expected to reveal its widespread occurrence west of the Narrows, wherever there are shores suitable for it.
The short lists of marine Mollusca from the Narrows and from Indian Harbour (C. pp. 1988 and 1989) include some European species. Of the bivalves Mya arenaria (sand mussel) and Mytilus edulis (edible mussel) extend in Randers Fiord into water with salinity as low as 5 to 6 ; of the Gastropods the common periwinkle (Littorina littorea) lives in the Randers Fiord in water of salinity 12 to 15, and the whelk (Buccinum undatum) in water of salinity 15 to 20. The last-named descends to considerable depths, so that for it, as for the others, the water in the greater part of the Hamilton Inlet beyond the Narrows is quite salt enough.
FLORA OF HAMILTON INLET.
The plants generally known as sea-weeds are fixed or attached marine algæ, a group of primitive plants that are primarily aquatic. Some sea-weeds live between tide-marks, others in deeper water ; they are most abundant on rocky shores, where there is a firm surface for their attachment. Marty species tolerate a reduced salinity of the water ; for example, the Baltic has a considerable and varied sea-weed flora (cf. Hauck, Marine Algæ of Germany and Austria, Leipzig, 1885, and Svedelius, Studies of the Baltic Marine Algal-Flora, Upsala, 1901). Of the brown sea-weeds belonging to the Fucaceæ Hauck lists eight species for the North Sea, four of which occur in the Baltic. From these general considerations it seems that the inner part of Hamilton Inlet should have a sea-weed flora ; but there is no information on this point. Dr. Kindle tells us that a species of Fucus and the large kelp disappear from the shore west of the Narrows ; but does not the rocky shore suitable for them disappear here also ?
Completely aquatic plants, with floating or submerged leaves, are found in fresh water ; some of these are algæ and some are members of a higher group, the flowering plants ; water-plants belonging to this group are secondarily aquatic, derived from land-plants. Dr. Kindles list of flowering plants “ believed to be adjusted to a coast-wise, lake-shore, or river habitat,” includes not more than half-a-dozen that are completely aquatic (e.g., Potamogeton heterophyllum, Ranunculus reptans, Callitriche palustris, from
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Grand Lake and the Naskaupi River) and none of these is from the region between the Narrows and the mouth of Hamilton River ; there is no information at all as to the water-flora of this area.
The rest of the plants in the list may be roughly divided into two main categories. One of these includes plants that are found in marshy soil and along the edges of lakes and rivers. The other division includes the halophytes, most of which cannot well be described as “ water-loving,” as their adaptations to a habitat near the sea consist of devices for doing with as little water as possible, so that they do not take in much salt. The halophytes are a very mixed group, including plants that live at varying distances from the sea and on different kinds of soil. Dr. Kindle states that seven of the species in his list do not extend west of the Narrows, and he names three of them. On turning to the list we find that one of the three is “not common west of the Narrows.” A second was found near Rigolet, but was “ not seen elsewhere ” ; the presence of this species at this particular spot and its absence elsewhere hardly justify any general conclusions. The third species was “ not seen above the Narrows,” but is correctly described as having a fresh-water and brackish habitat. These three species (Polygonum viriparum, Ranunculus lapponicus, and Iris setosa) are all widely distributed northern plants, and none of them is confined to the sea-shore. The Polygonum is a mountain species that extends southwards in America to the summits of mountains in New England. Ranunculus lapponicus is recorded in North America from the shores of inland fresh-water lakes, such as Lakes Nipigon and Superior. Iris setosa grows in a variety of soils, generally near fresh or brackish water, but sometimes in poor, dry sand. It is extraordinary that Dr. Kindle should write of these species that “ the inability of these salt-loving plants to extend their range west of the Narrows affords very clear botanical evidence of the change that takes place in the salinity of the water west of the Narrows.”
The evidence from the distribution of plants on or near the shores is so inconclusive and so remotely related to the question at issue that it does not demand further consideration.
CONCLUSION.
The general purport of the biological evidence put forward in support of the Canadian Case is to suggest that the marine fauna and flora do not extend beyond the Narrows owing to the reduced salinity of the water. I have disproved this contention by showing that the species specially selected to illustrate it are found elsewhere in water of salinity as low as, or lower than, that of the Hamilton Inlet west of the Narrows.
It is admitted that the fauna and flora of the Narrows may be in part absent from the region immediately to the west, which would seem to be unsuitable for some of the species owing to its great depth and the steepness of the shores ; this admission would not, of course, include animals that swim at the surface or in mid-water, or floating plants.
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Dr. Kindle seems to have been so sure that salinity was responsible for the apparent disappearance in this region of certain species found in the Narrows that he did not think it worth while to find out whether they reappeared in the more shallow areas further west, in which the salinity is considerably higher than in the Baltic, where some of these species occur. The most striking feature of his report is the absence of any positive evidence as to the nature of the fauna and flora of the Hamilton Inlet west of the Narrows ; he does not record a single animal that he has obtained, nor one completely aquatic plant that he has found in this area.
In the absence of any information it may be assumed, from what happens in waters of like salinity elsewhere, that a marine fauna and flora extends nearly to the mouth of the Hamilton River.
C. TATE REGAN.
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