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The Diatomaceæ associated with these shells include Coscinodiscus lineatus and species of Gallionella, Eunotia, Cocconeis and Achnanthes, most of them apparently identical with forms figured by Bailey. There are also minute acicular spicula of sponges.
Since the highest points at which raised beaches have been found in Canada scarcely reach an elevation of 80 fathoms above the sea level, we can scarcely expect to find on the present land evidence of depths equal to those represented by these soundings. Their containing distinct species from those in the tertiary clays is, however, an interesting fact, and I figure these as a guide to collectors who may be so fortunate as to find them in a fossil state.
(3.) Species of Bryozoa.
From the abundance of the remains of these creatures on stones at the surface of the boulder clay at Beauport, I have no doubt that a number of species might reward a diligent search. My time however at this locality was very limited, and although I brought thence single pebbles with as many as four or five species attached to them, I have no doubt that my collection includes only a small fraction of the species occurring there. The specimens are also in many instances in a defective state of preservation; and as collectors of these objects well know, even in recent specimens it is often very difficult to determine species from the dead cells alonc. I am therefore able to name at present only a few species, but these, I trust, may be relied on with soine cer
1. Hippothoa catenutaria, Fleming. (Fig. 12.)—This pretty little organism spreads its chains of cells over the tertiary pebbles at Beauport, just as is now does in the Gulf of St. Lawrence; and being of a dense and strong texture, is remarkably well preserved. It belongs at present to the Laminarian and Coralline zones, and is found abundantly in Gaspé Bay in nine fathoms.
2. Hippothoa divaricata, Lamour. (Fig. 13.)—This smaller and more delicate species is very abundant at Beauport; but from its minuteness and its similarity in color to the grey, weathered pebbles, may easily escape observation. It differs from the typical form of the species in having the cells united to each other directly, instead of by a slender calcareous thread; but as Johnston* mentions this as sometimes occurring in recent specimens
Fig. 14. it may be regarded as merely the characteristic of a variety*. I kave not yet found this species living in the Gulf of St. Lawrence.
3. Tæbulipora flabellaris, Fabricius. (Fig. 14.)- I refer-with some doubt-to this species the organism represented in kg. 14, which occurs sparingly and not in good preservation on stones at Beauport. Fabricius found this species in Greenland, and it occurs in various parts of the North Atlantic. I have not found it living, but it may be the same with the T. divisa, a species closely allied to flebellaris, found by Stimpson in the Bay of Fundy.
4. Lepralia hyalina, Lin. (Fig. 15.)—The organism represented in fig. 15 must, I think, be referred to this species. It is found sparingly on stones at Beauport, often nearly covered with the remains of its ovicapsules. It now lives in the Gulf of St. Law. rence and the Banks of Newfoundland.
5. Lepralia pertusa, Johnston. (Fig. 16.)—This species is
• British Zoophytes, page 292.
Vol. IV. No. 1.
very abundant at Beauport, and, as usual with it, is very variable. The cells represented in fig. 16 belong to the most regular and beautiful variety, which occurs in a state of preservation quite equal to recent specimens. L. pertusa is still one of the most abundant forms on the American coast ; and the study of the diverse forms of cells which occur in the same patch, is very instructive in relation to the errors likely to arise from basing specific distinctions in these creatures on minute differences in the forms of the cells.
The two last species appear to the naked eye on the stones of the drift, as flat, roundish, white patches, somewhat roughened, like sbagreen; and under a lens of low power disclose the forms of their cells.
Fig. 17. 7. Lepralia quadricornuta. N. S. (Fig. 17.)—This is a large species, the cells being about sth of an inch in length. It is quite distinct from any species known to me. Its description is as follows :—Cells arranged alternately, ovate, ventricose, smooth on the greater part of the surface, but toward the lower end finely marked with radiating and transverse lines, and at the margins roughened with scaly projections; aperture narrowed, lattened at the distal margin, and armed with four hollow spines, those at the angles strongest; proximal margin deeply sinuated and pro jecting.
The specimens occur abundantly in the lowest part of the deposit at Logan's farm, and are arranged in such a manner as to show that they were attached to fronds of algæ which have entirely disappeared. Being imbedded in soft clay, it is much more difficult to secure perfect specimens than in the case of the species attached to stones. From the position of this Lepralia in the deposit, I infer that it lived in very deep water; and it is possible that when we are better acquainted with the deeper parts of the Gulf of St. Lawrence, it may be found there. Having searched in vain for any described species corresponding with it, I propose for it the name of L. quadricornuta, founded on its most obvious distinctive character, which is of more importance - here than in the case of a recent species, owing to the circumstance that the specimens in the clay usually split in such a manner as to show only the inside of the cells, on which the four horns generally remain sufficiently distinct.
Patches of this Lepralia one inch in length and half an inch in breadth were found at Logan's farm, and the cells were remarkably uniform in size and shape. If found in a living state, its large size and elegant vase-like form will render it one of our finest species. Its nearest allies appear to be L. ventricosa, Hassell, L. trispinosa, Johnston, and L. crassispina, Stimpson.
Before leaving the Bryozoa, it may be well to name the additional species known to me as living in the Gulf of St. Lawrence and likely to occur in the drift :
Membranipora pilosa, Gaspé, Nova Scotia.
Through the kindness of Andrew Dickson, Esq., I was lately favored with the inspection of a flat stone taken up by the hook of a fisherman on the Banks of Newfoundland, which wonderfully resembles, in its assemblage of species, the stones in the drift at Beauport. It has at one end a group of Balanus crenatus of the precise variety so common in the drift ; and over various parts of the surface are abundant shells of Spirorbis sinistrorsa, with at few of another species not as yet found in the drift. Large portions of the surface are covered with Lepralia-variolosa and
hyalina ; and there is also a Tubulipora closely resembling that found at Beauport. The shell of a dead Balanus contained a little fine sand, among which were small and much rubbed speci. mens of a Polystomella or Nonionina, and fragments of spines of Echini. This stone is indeed almost a precise modern counterpart of those buried in the drift at Beauport; and they, like it, probably lay in the bottom of a sea loaded in spring with boulder-bearing ice.
I had almost omitted to mention that some of the stones from Beauport, with Balanus, Bryozoa, &c., bear on their surfaces distinct marks of glacial action, in their polish and striation ; and that just as in exposed situations in modern seas, their animal tenants have evidently selected the re-entering angles, and least exposed surfaces for their habitations. II. FRESH-WATER SHELLS IN THE POST-PLIOCENE DEPOSITS.
I have on several occasions found specimens of Limnea in the Post-pliocene clays, but always suspected some accidental intermixture. I have been favoured in the past summer, by Andrew Dickson, Esq., with specimens of land and fresh-water shells from the bank of a brook emptying into the Mississippi, a tributary of the Oltawa, two miles below Pakenbam Mills, and at an elevation of about 266 feet above Lake St. Peter. They were found in sand and gravel containing Tellina Grænlandica, and which Mr. Dickson thinks is an undisturbed tertiary deposit. The specimens furnished to me afford many internal evidences which would lead me to the same conclusion. The species present are :
Valvata tricarinata, Planorbis parvus,
Helix striatella ?
Lymnea elodes ? As may be seen by reference to the paper by Mr. Billings in the first volume of this journal, all these shells now exist in the Ottawa valley. Proof of their existence there in the Post-pliocene era would be of great interest; and though I am fully aware of the many chances that may cause recent fresh-water shells to be mixed with older deposits, I am strongly inclined to believe that these deposits at Pakenham afford such evidence. Their occurrence is at least deserving of notiee, that the attention of geologists may be attracted to the locality.