as in other allied forms, but half-closed by the bending back of the shell upon itself. Looking at the mouth of this shell, one might think that for half its extent it had been closed by a septum, the direction of which is symmetrical and inverse to that taken by the septum of the body chamber. On first examining these specimens, I was inclined to think that half the aperture was closed by a loosened septum; but further observations in eight or ten individuals shewed that it could not be an accidental condition, and lastly I found a specimen in which the whole circumference of the mouth could be traced with certainty. This semiclosure of the orifice of the shell in Gyroceras, appears, therefore, to be analogous to the contraction of the mouth in Pragmoceras, Gomphoceras and Lituites, above mentioned; but is peculiar in this, that it is not the lateral margins that are bent towards each other, as in these genera, but only the inner (under) margin is pressed back, (Journal of the Geological Society, Vol. 10, p. 23, of Miscellanies.) 8. Trochoceras. Figs. 8 and 9 represent two forms of this genus, the tube is coiled with a double curve like that of a snail, and the whorls are either in contact as in Fig 8, or separate as in Fig. 9. 9. Ascoceras. In this genus that portion of the shell which contains the air chambers, appears to be turned upwards, and recessed into one side of the body chambers. A small portion of it only remains at the bottom as seen at the base of Fig. 12. The siphon in specimens denuded of the shell can also be seen at the base. This genus has been recently discovered in the lower Silurian Rocks of this country, by Mr. Richardson, of the Geological Survey of Canada. Fig. 10, is a longitudinal section of an Orthoceras with a large marginal siphuncle. The spaces marked with the letter O, are the air chambers. A A A the large chamber of habitation which according to the views of M. Barrande, the distinguished palæontologist of Bohemia, extended into the siphuncle. In the lower part of the siphuncle is a space marked B of a lighter colour. M. Barrande is of opinion that certain species of this genus secreted a calcareous matter in the siphon which at length partially filled the tube. The letters B B indicate the position of this deposit in the specimen figured which is the Orthoceras communis of Europe. Professor Hall considers the Orthoceratites of the Trenton limestone, with these large marginal siphons to be gene. rically different from Orthoceras proper, and has accordingly constituted a new genus Endoceras, for their reception. Another genus quite common in the Black River limestone of Canada, is Gonioceras, (Hall.) But a single species is known (Gonioceras anceps,) and it is remarkable for its form, almost flat like a two edged sword. We shall give figures of this and other species in a future article. There are many species of Orthoceras in the Silurian Rocks of Canada, not yet named, and owing to the close resemblance of some of these, and also to the fact that they generally occur in mere fragrents, it is most difficult to identify them, or to decide whether they are new species or not. It will probably be many years before materials will be collected to complete this part of the Ancient Natural History of the Province, and we would therefore earnestly recommend all public Institutions in their exchanges not to part with any of their Orthoceratites, for it is only by combining the light afforded by all the collections that the Cephalopoda of the Silurian Rocks of Canada can be worked out. It is also very desirable that gentlemen in possession of these relics should publish short descriptions of their specimens, in one of the scientific journals of the Province. This remark applies to every other department of Natural History. In fact, there is not one single species either recent or extinct concerning which, there is not yet much to be made known. Every little fact, therefore, no matter how unimportant it may appear at the time to the observer, is to a greater or less extent of value, and should be communicated for publication. Fig. 11, is a transverse section of the specimen represented by Fig. 10, at the line from Y to X. It shews the siphuncle with the thickness of the calacerous secretion upon the inner surface. A small Orthoceras is shewn in the siphon of Fig. 10, into which it had found its way after the death of the larger individual. The figures have all been copied from the Bulletin of the Geological Society of France, of January, 1855. ARTICLE XVIII.-Notes on the Land Birds observed round Montreal during the winter of 1856-7, by W. S. M. D'URBAN. The late winter having been one of a very remarkable character, whether we consider the severity of some portions, or the unusual mildness of others, I am induced to offer for insertion in the Canadian Naturalist and Geologist, a few remarks on the Land Birds observed by me, in my ornithological rambles in the immediate neighbourhood of Montreal, from November 1st to March 31st, and which I hope may not be found altogether uninteresting. I have mentioned three species, viz: the Robin, Snow bird and American Shrike, which can hardly be considered as winter residents here, but are noticed because stragglers remained for some time after the cold weather had set in. The total number of species which wintered round Montreal exclusive of these three, is 15. The number mentioned as wintering in the neighbourhood of Toronto in a paper by G. W. Allan, Esq., published in the "Canadian Journal," for March 1853, is 24. Of these the following twelve, viz: Bald Eagle, Pigeon Hawk, Great Horned Owl, Little Horned Owl, Goldfinch, Tree Sparrow, Common Crossbill, Canada Jay, Red Bellied Nuthatch, Hairy Woodpecker, Quail, Canada Grouse, were not observed by me near Montreal during the winter months Two species which wintered here, viz: Hawk Owl and Brown-creeper, are not mentioned as occurring about Toronto. Observations extending over several years would doubtless add considerably to the number of species which pass the winter in the neighbourhood of Montreal. In the following notes I have adhered to the nomenclature and arrangement adopted in Audubon's Synopsis of the Birds of North America. Surnia funerea-Gmel.-Hawk Owl. I met with one of this owl November 19th, 1856. It was sitting in a tree in an open field by the side of the Mile-End Road, and though the sun was shining brightly, did not appear to be at all inconvenienced by the bright light. It was shy and restless, frequently changing its place, and often dropping down from the tree to the ground and flying up again. It flew off before I could get within shot and crossed the road in front of me. Not wishing to lose a chance, I fired, but without success, being too far off. Before I could reload, it again crossed the road and pitched in a tree near were I first saw it, and after some trouble I obtained a shot and wounded it. Although much hurt in its wing and body it flew across a field before I could secure it. I placed my gun upon it as it lay on the gound and it remained quite motionless till I attempted to kill it when it fought fiercely and struck its claws into my hand. Its flight was low and had great resemblance to that of a Hawk, for which I at first mistook it. Its stomach contained the fur of mice. I received another specimen from Laprairie which was shot in December. On 27th February, about sunset, I saw one sitting on the top of a tree in a small wood also near Mile-End road, and was just about to fire at it, when a hare ran past me which I shot. The report of the gun frightened the Owl and it flew away and I lost sight of it. Presently, however, seeing a large flock of Crows pitched on some trees about half a mile off I went towards them and found them mobbing the Owl which was sitting motionless in the top of a very high tree. I fired at it, and though apparently struck by the shot, it took no notice beyond shaking itself and turning its head to look down at me. I then gave it another shot and it fell half way down the tree, but recovering itself flew away and disappeared behind some bushes. Although this bird has somewhat the appearance of a Hawk, yet there is no Owl with which I am acquainted in which the formation of the breast-bone and merry thought differs so much from that which obtains amongst the Falconidæ. The sternum is very weak and the forked-bore, consists of two separate pieces, only united at their apices by a slight cartilage, I am not aware that this fact has been previously noticed by ornithologists, and I can find no mention made of it in the works of Wilson, Audubon, Richardson or Yarrel. Surnia nyctea. Linn. Snowy Owl. I saw only one of this Owl alive during the winter. On 17th January, one of the coldest days of the season, I walked across the ice to Nun's Island, and saw a Snowy Owl sitting on an isolated branch of a tree, near the farm yard attached to the Convent. It was so very shy I could not get near it. I visited the island several times afterwards in hopes of obtaining a fair shot at it, but was always unsuccessful, and it disappeared when the mild weather set in about 6th February. When I reached the island it was invariably exactly in the same spot, looking like a lump of snow in the tree, but whenever I attempted to get within shot; it would fly off and pitch on a fence, always shifting its place as I approached. The whiteness of its plumage rendered it very difficult to be seen when flying over the snow, and one day it flew pa t me without my seeing it till close to me, and was out of shot before I could draw off my mit to pull the trigger. Once I tried the expedient of putting a white shirt over my clothes, unfortunately, a friend with me not made similarly invisible, frightened it off before I got within shot. It probably subsisted on the rats in the farm yard, |