tion to be mixed with Erian fossils. It is to be observed, however, that the non-occurrence of any similar wood in all the formations between the Upper Erian and the Middle Cretaceous suggests very grave doubt as to the authenticity of the specimen. I record the fact, waiting further discoveries to confirm it. Of the character of the specimen which I have described I entertain no doubt.

We shall be better able to realise the significance and relations of this ancient flora when we have studied that of the succeeding Carboniferous. We may merely remark here on the fact that, in these forests of the Devonian and in the marshes on their margins, we find a wonderful expansion of the now modest groups of Rhizocarps and Lycopods, and that the flora as a whole belongs to the highest group of Cryptogams and the lowest of Phanogams, so that it has about it a remarkable aspect of mediocrity. Further, while there is evidence of some variety of station, there is also evidence of much equality of climate, and of a condition of things more resembling that of the insular climates of the temperate portions of the southern hemisphere than that of North America or Europe at present.

The only animal inhabitants of these Devonian woods, so far as known, were a few species of insects, discovered by Hartt in New Brunswick, and described by Dr. Scudder. Since, however, we now know that scorpions as well as insects existed in the Silurian, it is probable that these also occurred in the Erian, though their remains have not yet been discovered. All the known insects of the Erian woods are allies of the shad-flies and grasshoppers (Neuroptera and Orthoptera), or intermediate between the two. It is probable that the larvae of most of them lived in water and fed upon the abundant vegetable matter there, or on the numerous minute crustaceans and There were no land vertebrates, so far as known, but there were fishes (Dipterus, etc.), allied to the mod

worms.

ern Barramunda or Ceratodus of Australia, and with teeth suited for grinding vegetable food. It is also possible that some of the smaller plate-covered fishes (Placoganoids, like Pterichthys) might have fed on vegetable matter, and, in any case, if they fed on lower animals, the latter must have subsisted on plants. I mention these facts to show that the superabundant vegetation of this age, whether aquatic or terrestrial, was not wholly useless to animals. It is quite likely, also, that we have yet much to learn of the animal life of the Erian swamps and woods.

NOTES TO CHAPTER III.

I.-CLASSIFICATION OF SPORANGITES.

It is, of course, very unsatisfactory to give names to mere fragments of plants, yet it seems very desirable to have some means of arranging them. With respect to the organisms described above, which were originally called by me Sporangites, under the supposition that they were Sporangia rather than spores, this name has so far been vindicated by the discovery of the spore-cases belonging to them, so that I think it may still be retained as a provisional name; but I would designate the whole as Protosalviniæ, meaning thereby plants with rhizocarpean affinities, though possibly when better understood belonging to different genera. We may under these names speak of their detached discs as macrospores and of their cellular envelopes as sporocarps. The following may be recognized as distinct forms:

1. Protosalvinia Huronensis, Dawson, Syn., Sporangites Huronensis, "Report on Erian Flora of Canada," 1871.-Macrospores, in the form of discs or globes, smooth and thick-walled, the walls penetrated by minute radiating pores. Diameter about one one-hundredth of an inch, or a little more, When in situ several macrospores are contained in a thin cellular sporocarp, probably globular in form. From the Upper Erian, and perhaps Lower Carboniferous shales of Kettle Point, Lake Huron, of various places in the State of Ohio, and in the shale boulders of the boulder clay of Chicago and vicinity. First collected at Kettle Point by Sir W. E. Logan, and

in Ohio by Prof. Edward Orton, and at Chicago by Dr. H. A. Johnson and Mr. B. W. Thomas, also in New York by Prof. J. M. Clarke.

The macrospores collected by Mr. Thomas from the Chicago clays and shales conform closely to those of Kettle Point, and probably belong to the same species. Some of them are thicker in the outer wall, and show the pores much more distinctly. These have been called by Mr. Thomas S. Chicagoensis, and may be regarded as a varietal form. Specimens isolated from the shale and mounted dry, show what seems to have been the hilum or scar of attachment better than those in balsam.

Sections of the Kettle Point shale show, in addition to the macrospores, wider and thinner shreds of vegetable matter, which I am inclined to suppose to be remains of the sporocarps.

2. Protosalvinia (Sporangites) Braziliensis, Dawson, " Canadian Record of Science," 1883.-Macrospores, round, smooth, a little longer than those of the last species, or about one seventy-fifth of an inch in diameter, enclosed in round, oval, or slightly reniform sporocarps, each containing from four to twenty-four macrospores. Longest diameter of sporocarps three to six millimetres. Structure of wall of sporocarps hexagonal cellular. Some sporocarps show no macrospores, and may possibly contain microspores. The specimens are from the Erian of Brazil. Discovered by Mr. Orville Derby. The formation, according to Mr. Derby, consists of black shales below, about three hundred feet thick, and containing the fucoid known as Spirophyton, and probably decomposed vegetable matter. Above this is chocolate and reddish shale, in which the well-preserved specimens of Protosalvinia occur. These beds are very widely distributed, and abound in Protosalvinia and Spirophyton.

3. Protosalvinia (Sporangites) bilobata, Dawson, "Canadian Record of Science," 1883.-Sporocarps, oval or reniform, three to six millimetres in diameter, each showing two rounded prominences at the ends, with a depression in the middle, and sometimes a raised neck or isthmus at one side connecting the prominences. Structure of sporocarp cellular. Some of the specimens indicate that each prominence or tubercle contained several macrospores. At first sight it would be easy to mistake these bodies for valves of Beyrichia.

Found in the same formations with the last species, though, in so far as the specimens indicate, not precisely in the same beds. Collected by Mr. Derby.

4. Protosalvinia Clarkei, Dawson, P. bilobata, Clarke, " American Journal of Science."-Macrospores two-thirds to one millimetre in

diameter. One, two, or three contained in each sporocarp, which is cellular. The macrospores have very thick walls with radiating tortuous tubes. Unless this structure is a result of mineral crystallisation, these macrospores must have had very thick walls and must have resembled in structure the thickened cells of stone fruits and of the core of the pear, or the tests of the Silurian and Erian seeds known as Pachytheca, though on a smaller scale.

It is to be observed that bodies similar to these occur in the Boghead earthy bitumen, and have been described by Credner.

I have found similar bodies in the so-called "Stellar coal" of the coal district of Pictou, Nova Scotia, some layers of which are filled with them. They occur in groups or patches, which seem to be enclosed in a smooth and thin membrane or sporocarp. It is quite likely that these bodies are generically distinct from Protosalvinia.

5. Protosalvinia punctata, Newton, "Geological Magazine,” New Series, December 2d, vol. ii.-Mr. Newton has named the discs found in the white coal and Tasmanite, Tasmanites, the species being Tasmanites punctatus, but as my name Sporangites had priority, I do not think it necessary to adopt this term, though there can be little doubt that these organisms are of similar character. The same remark may be made with reference to the bodies described by Huxley and Newton as occurring in the Better-bed coal.

In Witham's "Internal Structure of Fossil Vegetables," 1833, Plate XI, are figures of Lancashire cannel which shows Sporangites of the type of those in the Erian shales. Quekett, in his "Report on the Torbane Hill Mineral,” 1854, has very well figured similar structures from the Methel coal and the Lesmahagow cannel coal. These are the earliest publications on the subject known to me; and Quekett, though not understanding the nature of the bodies he observed, holds that they are a usual ingredient in cannel coals.

II. THE NATURE AND AFFINITIES OF PTILOPHYTON.

(Lycopodites Vanuxemii of "Report on Devonian and Upper Silurian Plants," Part I., page 35. L. plumula of "Report on Lower Carboniferous Plants," page 24, Plate I., Figs. 7, 8, 9.) In the reports above referred to, these remarkable pinnate, frond-like objects were referred to the genus Lycopodites, as had been done by Goeppert in his description of the European species Lycopodites pennaformis, which is very near to the American Erian form. Since 1871, however, there have been many new specimens obtained, and very various opinions expressed as to their affinities. While Hall has named some of them Plumalina, and has regarded them as animal

structures, allied to hydroids, Lesquereux has described some of the Carboniferous forms under the generic name Trochophyllum, which is, however, more appropriate to plants with verticillate leaves which are included in this genus. Before I had seen the publications of Hall and Lesquereux on the subject, I had in a paper on "Scottish Devonian Plants "* separated this group from the genus Lycopodites, and formed for it the genus Ptilophyton, in allusion to the featherlike aspect of the species. My reasons for this, and my present information as to the nature of these plants, may be stated as follows:

Schimper, in his "Palæontologie Vegetale" (possibly from inattention to the descriptions or want of access to specimens), doubts the lycopodiaceous character of species of Lycopodites described in my published papers on plants of the Devonian of America and in my Report of 1871. Of these, L. Richardsoni and L. Matthewi are undoubtedly very near to the modern genus Lycopodium. L. Vanuxemiï is, I admit, more problematical; but Schimper could scarcely have supposed it to be a fern or a fucoid allied to Caulerpa had he observed that both in my species and the allied L. pennæformis of Goeppert, which he does not appear to notice, the pinnules are articulated upon the stem, and leave scars where they have fallen off. When in Belfast in 1870, my attention was again directed to the affinities of these plants by finding in Prof. Thomson's collection a specimen from Caithness, which shows a plant apparently of this kind, with the same long narrow pinnæ or leaflets, attached, however, to thicker stems, and rolled up in a circinate manner. It seems to be a plant in vernation, and the parts are too much crowded and pressed together to admit of being accurately figured or described; but I think I can scarcely be deceived as to its true nature. The circinate arrangement in this case would favour a relationship to ferns; but some lycopodiaceous plants also roll themselves in this way, and so do the branches of the plants of the genus Psilophyton. (Fig. 17, supra.)

The specimen consists of a short, erect stem, on which are placed somewhat stout alternate branches, extending obliquely outward and then curving inward in a circinate manner. The lower ones appear to produce on their inner sides short lateral branchlets, and upon these, and also upon the curved extremities of the branches, are long, narrow, linear leaves placed in a crowded manner. The specimen is thus not a spike of fructification, but a young stem or branch in vernation, and which when unrolled would be of the form of those

* "Canadian Naturalist," 1878.