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points to a still higher differentiation so characteristic of the later genera of the Equine series. The characters above enumerated as distinguishing the molars of Pachynolophus from those of Hyracotherium, I think should be considered as generic. At least they are the only

valid ones which I can discover at present.

Species of Perissodactyle Ungulatus allied to Hyracotherium occur in the Wasatch of America, which have been referred to Pachynolophus. In these forms the last inferior premolar is truly molariform, but the superior molars are of the primitive type namely; with low crowns and nearly bunodont external cusps. As this a combination of characters, which as far as known does not occur in the true Pachynolophus of Europe, I think accordingly that these species should be placed in a different genus from Pachynolophus. Prof. E. D. Cope has shown that the generic name Orotherium Marsh, has been anticipated by Orotherium Aymard, consequently I believe that the name Orohippus should be reinstated, and applied to those species of Hyracotherium which have the last lower premolar truly molariform in structure. I have already stated that in the type specimen of Hyracotherium (=Pliolophus) vulpiceps the last lower premolar is simpler in structuré than in any of the true molars. Accordingly those species with the complex lower premolar represent a true generic stage, and as is already shown they differ from the true Pachynolophus.-CHARLES EARLE, Laboratoire de Paleontologie Jardin des Plantes, Paris, Dec. 20, 1895.

The Glossopteris Flora in Argentina.-A collection of fossil plants from Bajo de Velis, a league from the entrance to the Cantana valley in Argentina, has enabled Dr. F. Kurtz to establish the age of the fossiliferous shales of that region. The author gives tabulated comparisons of the flora of the Bajo de Velis beds with similar floras found at the Cape of Good Hope (Ekka-Kimberly beds), in peninsular India (Kaharbari beds), in New South Wales (Newcastle beds) and in Tasmania (Mersey Coalfield). From these tables it is seen than the specimens found at Bajo de Velis are most nearly related to those of the lower Gondwanas of India. Dr. Kurtz accordingly corrrelates the fossiliferous shales of Bajo de Velis with the lower Gondwanas of India, and agrees with the paleophytologist, O. Feist mantel, in assigning these beds to the Permian age.

Up to date but three rock formations in Argentina have yielded fossil plants: Retamito in San Juan, which has been shown by Dr. Szajnocha to be Lower Carboniferous; Bajo de Velis which is Permian; and

a series of beds in Mendoza, San Juan and La Rioja determined by Prof. Geinitz as Rhætic.

These data are commented on by the Director of the Geological Survey of India to the effect that one of the chief points of interest in connection with the discovery of Gondwana plants in Argentina lies in the fact that we have an unquestionable lower carboniferous series (Retamito) in the neighborhood of which (and probably unconformably to it) a series of beds is found, which contains well known Lower Gondwana species of plants, thereby limiting the geological range of the lowest beds of it, at all events to upper Carboniferous at most, which is a further confirmation of the views generally adopted by the Geological Survey of India. The genus Glossopteris proper is wanting, but the other genera characteristic of that flora are present. (Rec. Geol. Surv. Ind., Vol. XXVIII, 1895.)

Geological News.-PALEOZOIC -From a petrographic study of the igneous rocks near St. John, N. B., Mr. W. D. Matthew classifies the Pre-Cambrian of that region as follows: A. Laurentian composed of (1) Portland group and (2) Intrusive granite, B. Huronian composed of (3) Coldbrook group, of volcanic rocks, (4) Coastal group, of volcanic and sedimentary rocks, (5) Etcheminian or Basal Series, of sedimentary rocks, and (6) Kingston group, of metamorphosed volcanics. (New York Acad. Sci. XIV, 1895.)

MESOZOIC. In studying the fossils obtained by M. Gautier from Madagascar, M. Boule comes to the conclusion that the Jurassic deposits of eastern Africa and those of the western slopes of Madagascar appear to have been laid down in a great interior sea, an Ethiopian Mediterranean, which was separated from the Pacific by an Indo-Madagascar peninsula.

Furthermore, that during the Upper Cretaceous there was land communication between the African continent, Madagascar and Hindustan. (Bull. Mus. d'Hist. Nat. Paris, 1895.)

According to R. W. Ells, the whole range of North Mountain, which cuts off the valleys of Cornwallis and Annapolis rivers from the Bay of Fundy, is an overflow of igneus rock which has issued through a line of fissure transversing the red Triassic beds, and is, therefore more recent than the latter. At several places the trap is overlaid by newer sedimentary beds of limestones and shales. No fossils have as yet been found in these sedimentary strata. The author calls attention to their importance and the desirability of a thorough exploration in order to determine their age since they represent the highest group of stratified sedimentary rocks in Eastern Canada. (Trans. Nova Scotian Inst. Sci. Halifax, Vol. I, 1894, p. 416.)

Two new species of Fishes from the Rolling Downs Formation (Lower Cretaceous) of Queensland are described by A. S. Woodward. They represent species of the genera Portheus and Cladocyclus, to which he gives the names australis and sweetii respectively. This discovery of these fossils is of considerable interest, since with the exception of a few Selachian teeth and vertebræ, and a fine species of Belonostomus, no cretaceous ichthyolites of importance have hitherto been described from this colony. (Ann. Mag. Nat. Hist. (6) XIV, 1894, p. 444.)

CENOZOIC.-Fossil Ants are reported from the Bembridge limestone (Eocene) of the Isle of Wight. They are referred by P. B. Brodie to the genera Formica, Myrmica and Camponotus, and some others not yet described. The first two genera have also been found in the Baltic Amber. (Nature, 1895, p. 570.)

The Champlain epoch is correlated by Prof. Hitchcock with the Mecklenburg stage of Geikie. Both have the characteristic marine. mollusca fauna, the Arctic flora (Yoldia beds of the Baltic) and best illustrate the isobases of De Geer. (Bull. Geol. Soc. Amer., Vol. 7, 1895.)

VEGETABLE PHYSIOLOGY.'

Smut Fungi by Oscar Brefeld.-At last we have in two big quartos, with numerous plates, the long promised volumes on the smut fungi. The work which is here completed was begun more than 12 years ago. The earlier experiments were gathered together and published in 1883 in a volume of 220 pages with numerous plates under the title of Die Brandpilze I, forming Heft V of Dr. Brefeld's Untersuchungen, the most important and revolutionary portion of this volume being the demonstration that the smut fungi, a goodly number at least and presumably all of them, although previously supposed to be strictly parasitic were capable of growing saprophytically and of multiplying indefinitely in dung in the form of sprout conidia, closely resembling yeasts, if not identical with many forms previously referred to this group. Some years later in an address before the agricultural club of Berlin, Dr. Brefeld communicated the most important results of his

1 This department is edited by Erwin F. Smith, Department of Agriculture, Washington, D. C.

magnificent infection experiments, but now for the first time we have full details of all the laboratory and field investigations. In the limits of this review it will be possible to notice only the first of these two volumes. This forms Heft XI of the Untersuchungen and is entitled Die Brandpilze II. It deals principally with infection experiments and gives in full the results obtained with Ustilago Carbo on oats, U. cruenta on sorghum, and U. maydis on maize. These experiments were carried on through a period of four years with striking results and in case of corn, with most unexpected ones. Space forbids entering into Those who wish for details will naturally consult the

much detail.

volume itself.

Suffice to say that the infective material consisted of the yeast-like conidia propagated in nutrient solutions made from fresh horse dung.

In case of oats the best results from direct infection were 17 to 20 per cent. of smutty plants, obtained by spraying during the earliest stage of germination. Infections made when the embryo was one cm. long gave only 7 to 10 per cent of smutty plants; when it was 2 cm. long (500 plants), only 2 per cent became smutty. When the plumule had pushed through the enfolding sheath scarcely any of the plants could be infected, 200 seedlings in this stage yielding only 1 per cent of smutty plants and 200 more remaining entirely free. The infections took place through the young axis and also through the sheathing leaf so that both Wolff and Kühn were right, but a majority of the infections were through the young axis. In a second series of experiments garden earth was sprayed with the smut conidia and two days later oats were planted 1 cm. deep and subsequently transplanted to the open field: 300 of these seedlings yielded 5 per cent of smutty plants, and 300 more, 4 per cent., i. e. a much smaller per cent than was anticipated. In a third series fresh horse dung was mixed with garden earth which was then abundantly impregnated with the smut conidia. Three days later oats which had been soaked but were not yet germinated were planted in this soil at a depth of scarcely 1 cm. These seedlings were divided into two lots, 300 were kept for a time in the laboratory at a temperature of over 15°C., and 300 were placed in the cellar where the temperature did not exceed 7°C. Of the 300 kept in the laboratory 27 to 30 per cent finally became smutty; of those kept in the cellar, where germination proceeded more slowly, 40 to 46 per cent became smutty. This shows clearly that fresh horse dung greatly favors the development of smut and that weather which retards germination is also favorable. In the fourth series of experiments the infectious material was derived from conidia cultivated for a long time arti

ficially, a few of the spores being transferred to a fresh nutrient solution every four days. The first trial (500 seedlings) was with conidia which had been cultivated in this manner for six months. These seedlings yielded from 7 to 10 per cent of smutty plants. The second trial was with conidia which had been cultivated for a year. This experiment was almost wholly negative, 300 of the seedlings yielded no smutty plants and 200 more gave only 1 per cent. The explanation was not far to seek since at the end of this period the conidia had almost wholly lost the ability to send out germtubes and along with it the power to infect the plants. Microscopic examination showed that ⚫ the germtubes can penetrate into any part of the young seedling but this does not necessarily mean infection. The latter takes place only when the smut hyphæ are able to reach that part of the plant where the smut beds form. In all of these experiments the smut germs penetrated the young seedlings but the smut beds appeared only in the floral organs, some months intervening between the entrance of the fungus and the appearance of the smut in a totally different part of the plant. Those germtubes which enter the plant and fail to reach the incipient ovaries become enclosed in the mature tissues of the host plant and are incapable of further growth and this frequently occurs even in young seedlings.

The infections obtained with the big sorghum plant are even more interesting. Nearly all of the first series of infections were destroyed by a hail storm, but of the 32 plants which escaped 12 became smutty. The seedlings of the second series were infected indoor in March and set out the first of May. The plants grew luxuriantly and by the middle of August had reached a height of 5 to 7 feet. The first smutty panicle appeared August 16 and for some time thereafter it appeared as if all of the plants would be smutty, the infected panicles developing first. Finally sound ones began to appear. In the end there were 158 smutty plants out of 274. A third series of experiments was instituted to determine in what stage of germination the sorghum plant is most susceptible: 252 seedlings sprayed in the earliest stage of germination, gave 180 smutty plants. "The development of the smut in the earliest and strongest plants, which reached a height of 8 feet, was striking. The big panicles were attacked in toto and projected out of the luxuriant green foliage like black brooms." There can be no doubt that infection stimulates the growth of the plant. Older seedlings yielded less striking results: 150 which were infected when the embryo was a centimeter long, gave only 24 smutty plants; 190 infected when the embryo was 1 cm. long gave 12 smutty panicles; 221 infec

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