China, in particular to the mode of occurrence of the Devonian limestone.

I consequently visited the place a few days ago, on a journey overland from Ningpo to Ching-kiang. As no limestone of more recent age than the Devonian was heretofore known in China, I was much surprised to meet with nummulites almost at first sight, and afterward I found the rock in places nearly made up of them. The rock is well exposed to view by enormous quarries, which appeared to have been worked for an immensely long time. The weathered surface of those fragments covering the more ancient waste-dumps shows the structure of the shells with remarkable distinctness, even the minute pores being clearly recognizable with a glass, so that there can not be the least doubt in regard to the true character of the fossil. Several species of Nummulina appear to be represented, as is indicated by the differences in shape of the cross-sections. As Nummulites are characteristic only of one distinct part of the Eocene period, the fact of their occurrence should be sufficient evidence for the determination of the age of any rocks in which they are met with. But I found myself now in face of the strange fact, that it was partly on the strength of its fossils that the limestone in question had heretofore been considered as Devonian. I attempted therefore to collect its fauna more fully. I found the rock in places full of fossils, mostly bivalves and gasteropods, which have by no means a Paleozoic appearance. They are in an excellent state of preservation, the shells being only bleached. But the limestone is so hard and brittle that I destroyed nearly every specimen which I tried to save; yet I succeeded in getting a few good ones of bivalves. The forms of these fossils, as well as their state of preservation, reminded me much of similar occurrences in the Nummulitic limestone of Dalmatia. Besides gasteropods and bivalves, there occur corals and fragments of very large encrinites. Some of the former which I collected can probably be determined. But I failed to discover a single brachiopod, which are almost the only fossils supposed to be characteristic of the Devonian limestone of China. I presume that indistinct fragments of bivalves, which are usually all that can be obtained, have given rise to the belief of the occurrence of brachiopods on the Si-Tung-ting. Perhaps, too, real brachiopods may have been derived from other places in or near Tai-hu lake, as it is quite possible that true Devonian limestone may occur in the neighborhood.

The nummulitic limestone of Si-Tung-ting is very bitumin

It is burnt in kilns and emits a remarkably strong smell. Its thickness cannot be accurately determined, but it is certainly not more than six hundred feet. Its beds are nearly horizontal,

and rest on ancient sandstones, the strata of which are inclined at an angle of about twenty degrees. These sandstones are supposed by Mr. Kingsmill to have a thickness of about ten thousand feet.

Before visiting Si-Tung-ting, I had observed the occurrence of limestone in the neighborhood of the sea coast, near Hang-chau in the province of Che-Kiang, a place mentioned in Mr. Pumpelly's list of localities distinguished by the occurrence of useful minerals. As it rests there quite unconformably on sandstone similar to that which underlies it at Tung-ting, and has a similar lithological character, I believe that I may safely refer it to the same formation with that of Tung-ting. I shall hence look out for its further distribution in China. The subject is not without some practical interest, in a country where all limestone was assumed to underlie the coal and iron-bearing formations.

In 1861, the easternmost place where the Nummulitic formation was known to occur was northern India. I succeeded in that year in proving its existence so far east as Japan and the Philippines, a notice of which you may find in a paper published in the Jahrbuch der deutschen geologischen Gesellschaft of 1861 or 1862. I do not know whether the same formation has since then been found in the regions intermediate between those two countries and India. The occurrence in lake Tai-hu is one of the connecting links, and it is now quite likely that this interesting formation, occurring in places so far apart, is among the most widely distributed in Eastern Asia; and it is quite possible that one unbroken area of submergence may be proved to have extended during the short existence of the genus Nummulina, from Spain to the Philippines and Japan.

I may add, as a sort of voucher for the correctness of my observation, that its communication places me into the disagreeable position of taking opposite views from those of Mr. Kingsmill, a gentleman who has, besides his professional activity as architect in Shanghai, worked of late years with admirable success in the geology of some parts of China. He informed me, some time before I visited Tung-ting, that he had sent a paper on the geology of that locality to the London Geological Society, in the Journal of which it may be printed by this time. The views which he informed me he had taken therein are, that the limestone of Tung-ting is Devonian or Subcarboniferous, and that the great sandstone formation, which plays a very important part in the geology of Eastern China, preceded it in age. The relations observed at Si-Tung-ting do no longer justify this conclusion, after the discovery of the nummulites, and the age of the sandstone (Tung-ting-grits of Mr. Kingsmill) must therefore be considered as not yet safely

established. Mr. Kingsmill has, however, succeeded in collecting some remains of plants in the upper layers of the sandstone, and it is to be hoped that they will suffice to determine its age. The state of the weather prevented me from hunting for the locality where he found them.

ART. XIX.-Note on the Infusoria Flagellata and the Spongic Ciliate; by Prof. H. JAMES-CLARK, Kentucky University, Lexington, Ky.

I send this note in hopes that it may be of interest to those readers of this Journal who have followed the recent discussions upon spontaneous generation and the doctrine of evolution. It is an effort to clear up the chaos of uncertainty which has reigned among the lower Protozoa for years past, and particularly in the heterogeneous group of so-called Sponges. The aim of the Evolutionists is clearly, by refusing to recognize their truly organized structure, to depress these creatures to such a low level in grade, that they shall appear but a step above the lifeless protoplasm which some think has been seen almost manufactured in the laboratory of the chemist. hypothetically developing "organizable protoplasm" out of “inferior types of organic substances," which in the process, per se, under the mutual influences" of its metamorphic forms, generates still more sensitive organic matter, until it finally attains to the possession of vital actions, the evolutionist imagines himself able "deductively to bridge the interval" between the so-called "nascent life" and the unmistakable vitalism of the slimy Rhizopod (see Herbert Spencer, Appleton's Journal, Aug. 7th 1869, p. 598.)

After

My own researches have constantly tended in the opposite direction. In spite of the apparent physical simplicity of even the lowest of the Protozoa (Amoeba and the like), their habits and the phenomena attendant upon their mode of locomotion, their determinate prehensile acts, so wonderfully like consciousness of an end to be accomplished, and their undeniably specialized digestive functions, all lead to the conclusion, which with me is a fact, that they possess a degree of differentiation in esse as marked as that which we recognize as potential in the earliest stage of the vertebrate embryo. In the former, the organization is present, but not circumscribed into regions; in the latter it is also present uncircumscribed, but it is to be eventually differentiated. The Sponges, with their supposed slimy, protoplasm-like simplicity, have been in former years the hunting ground of the developmentalists, but of late, that

group has been slipping out from under the feet of those philosophers.

Carter first detected the true criterion of their animality, though erring as to their classificatory relationship. It was my good fortune to prove their close alliance with the Flagellata, in a memoir (Mem. Boston Soc. Nat. Hist., vol. i, pt. III, Sept. 1867, On the Spongia Ciliata as Infusoria Flagellata), published some few years ago. I described certain monad-like infusoria which possessed a single flagellum surrounded by a projecting membranous collar. Some forms were appended to branching stems (Codosiga) and others were ensheathed in a funnel-shaped or urnæform tube (Salpingoca). The monadiform body of these I showed to be identical with the ciliate bodies of one of the Spongiae Ciliata (Leucosolenia), and homologised the branching stem and the ensheathing tubes of the former with the gelatinous mass of the latter, into which its monads were imbedded. The connection seemed not even a step wide, so clear and unmistakable was the relationship. That there should ever be discovered a form which would lie so intermediate between these as to make me hesitate whether it belonged to the one or the other, I did not even hope for; but it has come unexpectedly. In Schultzes Archiv. für Mikroskopische Anatomie, (Bd. VI, 4, 1870), Cienkowsky describes, under the name Phalansterium, a genus which consists of monad-like bodies with a flagellum and a projecting collar like those of Codosiga, Salpingoca and Leucosolenia. Of the two species which he illustrates, one (P. consociatum) has monads enveloped in a broad funnelshaped, slimy sheath, and these sheaths are closely packed side by side, radiatingly, so as to form a shield-like or a hemispherical mass. This comes nearest to the Salpingoca. The other species (P. intestinum) possesses similar monads, but they are imbedded basally in a gelatinous, intestiniform mass of slime (Schleim) "with their vibrating lashes extending in every direction" about the cylindrical colony. Originally each monad is endowed with a separate slime-sheath; but eventually these all are fused together into one common mass. Beyond this, to make a true Sponge we need but the presence of spiculæ, and open interspaces in the slimy mass, between the monads, leading to one common cavity. Introvert the layer of monads and we produce the desired effect without doing violence to their relative positions. It is a mere matter of proportions, just as the inverted cyathiform rose-hip is none the less an ovariferous disc than the globular receptacle of the strawberry.

ART. XX.-Memoir of Thomas Graham; by Prof. JOSIAH P. COOKE, Jr.*

It would be difficult to find in the history of science a character more simple, more noble, or more symmetrical in all its parts than that of THOMAS GRAHAM, and he will always be remembered as one of the most eminent of those great students of nature, who have rendered our Saxon race illustrious. He was born of Scotch parents in Glasgow in the year 1805, and in that city, where he received his education, all his early life was passed. In 1837 he went to London as Professor of Chemistry in the newly established London University now called University College, and he occupied this chair until the year 1855, when he succeeded Sir John Herschel as Master of the Royal Mint, a post which he held to the close of his life. His death, on the 16th of September last, at the age of sixty, though occasioned by a severe cold, was really the wearing out of a constitution enfeebled in youth by excessive labor, voluntarily undertaken and courageously borne, that he might devote his life to scientific study. As with all earnest students, that life was uneventful, if judged by ordinary standards; and the records of his discoveries form the only materials for his biography. Although one of the most successful investigators of Physical Science, the late Master of the Mint had not that felicity of language or that copiousness of illustration, which added so much to the popular reputation of his distinguished contemporary, Faraday; but his influence on the progress of science was not less marked or less important. Both of these eminent men were for a long period of years best known to the English public as teachers of Chemistry, but their investigations were chiefly limited to physical problems; yet, although both cultivated the border ground between Chemistry and Physics, they followed wholly different lines of research. While Faraday was so successfully developing the principles of electrical action, Graham with equal success was investigating the laws of molecular motion. Each followed with wonderful constancy, as well as skill, a single line of study from first to last, and to this concentration of power their great discoveries are largely due.

One of the earliest and most important of Graham's investigations, and the one which gave the direction to his subsequent course of study, was that on the diffusion of gases. It had already been recognized that impenetrability in its ordinary sense is not, as was formerly supposed, a universal quality of matter. Dalton had not only recognized that aëriform bodies exhibit a positive tendency to mix, or to penetrate through each other, even in opFrom the Proceedings of the American Academy of Arts and Sciences, vol. viii, May 24, 1870.