Page images
[graphic][merged small]

1. Polystomella umbilicatula, Walker (Fig. 1).*—Nine tenths of the foraminifera from the Montreal clays belong to this species, which also occurs at Beauport, and in equal proportionate abundance living in Gaspé Bay. The specimens all belong to the variety incerta of Williamson; and as among many hundreds of specimens I can find none that present the typical characters of the species, and as the general form is also less compressed than in the typical specimens as described and figured by Williamson, I should be inclined to believe this so-called variety in reality a distinct species, were it not for the fact, that, while these curious little creatures are almost indefinitely variable, there is a remarkable persistency of certain varieties in particular localities. The modern specimens from Gaspé correspond precisely with their ancient progenitors of the Post-Pliocene clays. The size of the fossil specimens is large for the species; the diameter of some individuals being sth of an inch. .

Localities.- Logan's farm, Montreal; Brick-yards at Tanneries, Montreal ; Beauport; also recent in Gaspé Bay.

2. Nonionina crassula, Walker.—Among the fossil specimens of the last specieş, there are many not distinguishable from it in external form, in which I cannot find, either when viewed as opaque or transparent objects, the characteristic septal apertures of Polystomella. These specimens are usually smaller, more hyaline, and smoother than those showing the apertures. If distinct, they must belong to the species above named. I found no individuals of this description among my recent specimens from Gaspé.

• See also paper in Can. Nat. Vol. 2, Fig. 17.

3. Polymorphina lactea (Figs. 2, 3, also paper in Canad. Nat. vol 2). This is perhaps the second species in relative importance, though much less plentiful than Polystomella umbilicatula. The greater number of the specimens belong to the variety " typica" of Williamson (Fig. 2). Others appear to be an exaggerated form of the variety " oblonga" (Fig. 3), and many others, especially the smaller examples, are of the variety“ communis.A similar range of vari-ties exists in the modern specimens from Gaspé. Size zo to z'ó.

Localities.-Logan's farm ; Tanneries; rerent in Gaspé.


Fig. 2 Fig. 3. 4. Miliolina seminulum (Lin.)—(For figure, see paper in Can. Nat. Vol. 2, Fig. 18.) In my paper of last year this species was noticed as Quinqueloculina occidentalis, Bailey; and I still believe it to be identical with the shell so named; but I presume that it, as well as many other supposed species of the genus Quinqueloculina of D'Orbigny, must be included in Miliolina Seminulum, as extended by Williamson. This shell is not infrequent in the clays at Montreal, and it also Gaspé Bay. It approaches very nearly to the typical form of the species, but is usually of small size, not exceeding 'oth of an inch in length.

Locality.—Logan's farm.


Fig. 4.

Fig. 5. 5. Entosolenia globosa (Figs. 4, 5).—This species is not uncommon in the clay at Montreal. Fig, 21 of my paper of last year is

referable to it, as I had not then observed the internal tube, and supposed it in consequence to be an Orbulina. Figs. 4 and 5 show this internal structure. This species is very small, scarcely exceeding both of an inch, and is very smooth and translucent.

Locality.—Logan's farm; Tanneries.


Fig. 6. Fig. 7. 6. Entosolenia costata, Williamson (Figs. 6, 7; also Fig. 22 in paper of last year.)—This beautiful little shell differs from that last described only in the possession of longitudinal narrow ribs. Williamson, who had seen only two or three examples, establishes it as a separate species with some doubt; and since in my specimens from the Montreal clays the number and distinctness of the ribs are very variable, I think it probable that this shell is only a variety of E. globosa.

Locality as above.

[ocr errors]

Fig. 10.

Fig. 9. Fig. 8. 7. Entosolenia Squamosa (Figs. 8, 9, 10).—This, the most elegant of all our Post-Pliocene foraminifera, presents several beautifully ornamented varieties. In the last species the sides are marked by simple longitudinal ribs. In the simple varieties of this the ribs are crossed by more slender transverse bands In others the rectangular spaces thus formed appear to have circles inscribed in them. In others the distinction of longitudinal and transverse ribs disappears, and the whole surface be comes covered with a regular hexagonal network of raised lines of various degrees of fineness. I have endeavoured to represent several of these forms in the figures ; but there are many intermediate varieties, and my wood-cut representations fall far short of the exquisite beauty of the shells themselves, which appear under the microscope as if worked in pure translucent porcelain. Size Tóo to do

Parker and Jones regard the three species last described as identical. Williamson also leans to this view; and since in my specimens there is a gradation from those that are smooth to those that are ribbed, and from these to those that are netted, I can scarcely hesitate to adopt the same conclusion, in which case the two la-t species must be regarded as varieties of E. globosa.


Fig. 11. 8. Biloculina ringens, D'Orb. (Fig. 11).--I have found only two specimens of this species, and neither revealed much of its real character until mounted as a transparent object. I have figured one of them as it appears in this way; and it well shows the manner in which the successive cells are added, the orifice being alterna:ely at opposite ends of the shell. Size about y'o.

Localily.— Tanneries.

All the species of Foraminifera above noticel are found living as well as fossil. Three of them have been obtained by myself from Gaspé Bay, and the others may probably be found there. The species most abundant in the tertiary clars is also that which prevails in Gas; é Bray, and the conditions of life in both are the same. The Gaspé specimens were found in mrl, in from 10 to 15 fathoms, and holding Leda limatula, Tillin, culearen, auch Astarte sulcata, so that it may be regarded as strictly equivalerit to our Montre:1 Leda clay, in or at the surface of wbich the Foraminifera chiefly occur. Two species found at Gaspé have not as yet been recognized in the tertiary clays. One is a globular shell, probably Orbulina universa, the other a rough, punctured, yellowish species, probably Bulimina scabra.

All the species found in the Canadian tertiary clays are widely distributed in the North Atlantic, and some of them still more extensively. Polymorphina lactea is found in the British crag, * and Entosolenia globosa in Miocene deposits at Petersburgh, U.S.f They afford little indication of climate, Miliolina seminulum, for instance, extending in the present seas from Greenland to Cuba. With respect to depth of water, their indications are probably more precise, though on this subject I can find little reliable information. One fact is certain, that in Gaspé, at present, a depth of 10 to 20 fathoms corresponds bathymetrically, in so far as these creatures are concerned, with that represented by the upper layers of the Leda clay, or brick-clay of Montreal. I have obtained, however, at least one indication ilint there are still lower depths, not represented as yet by the fossils of our tertiary deposits.

I owe to the kindness of Capt. Orlebar, R. N., two small specimens of fine clay, taken up by the sounding-lead from depths of 187 and 196 fathoms, off Mount Camille, near Bic Island, in the River St. Lawrence. On carefully levigating these specimens, I found in them three species of Foraminifera, all distinct from those of the tertiary clays and of Gaspé, and the silicious shields of a number of microscopic plants (Diatomacev). The Foraminifera I refer to the following species :

Rotalina turgida, Williamson. (Fig. 20.)
Spiroloculina depressa, D’Orbigny. (Fig. 21.)
Bulimina auriculata, Bailey. (Fig. 22.)

[graphic][graphic][merged small][ocr errors][graphic][merged small][merged small][merged small][merged small]
« EelmineJätka »