flowers are visited by honey-bees, which barely insert their heads into the gorge of the flowers; the chin or throat of the bee, coming into contact with the lower lip of the corolla, is necessarily dusted with pollen from the older flowers; and this pollen, in the passage from flower to flower, and plant to plant, is inevitably applied to the stigma of the freshly opened flowers, which alone is in condition to receive it. The nectar sought by insects is here secreted abundantly by the corolla, at its base on the posterior side, and to some extent by the disk which girts the base of the ovary; the posterior face of the scale which represents the anther of the fifth stamen is apparently glandular, but hardly if at all nectariferous. Bees plunge their proboscis to the bottom of the flower.

A. G.

13. Transmutation of Form in certain Protozoa.-Mr. METCALFE JOHNSON has a paper on this subject, in the number for May, (No. 29), of the Monthly Microscopical Journal, (London), presenting views similar in some respects to those of Mr. Hilgard, (pages 20 and 88, of this volume). The following passages from the article present the general conclusion of the author.

In the Monthly Microscopical Journal' for April, 1870, I have ventured to remark that "Monas and its congeners become at once important as agents in removing dead cells, and in their place supplying us with green verdure which is springing up around us on every side." Everyone must have observed that universal greenness which, after the lapse of a few weeks, spreads more or less over every weather-exposed surface, large or small. Sir Humphrey Davy, writing forty years ago, says, "A polished surface of a building or a statue is no sooner rough than the seeds of lichens and mosses which are constantly floating in the atmosphere make it a place of repose, grow and increase." If we examine a few of the green growths upon these surfaces differing from one another in their surroundings, or "choses extérieures," such as moisture, light, temperature, &c., we shall find one composed of a green dust, to which the name of Chlorococcus has been applied; another, a green scum upon the surface of a liquid, which has received the name of Euglena; a third, forming patches of dark green slime upon old walls, and called Oscil latoria; a fourth, Lyngbya; a fifth, Vaucheria; a sixth, Schidzonema, and so on. A more detailed examination of these separately-named products, and a study of their life-history, leads to the opinion that they are all (more or less) stages of development of some one common source, which it is the object of the present remarks to identify as the monad, or pin-point, source of life, which has been pointed out by Dr. Bastian and others as the earliest form in which we recognize living matter.

In order to commence this investigation I will append a few observations I have made on various forms of Paramecium, and I shall endeavor to show that it constantly transforms to Vorticella, and thence passes to Callidina elegans, thus tracing one of the phases of growth by development from the simple form of Monas to some of the more complicated animalculæ or Entomostraca.

I

shall hope in a future communication not only to trace the Paramæcium from the monad, but also to show that the "choses extérieures being altered the monad may become a Chlorococcus, an Oscillatoria, a Lyngbya, a moss, a lichen, an Amaba, or a Mucedo.

14. Embryological Studies on Diplax, Perithemis, and the Thysanurous genus Isostoma; by A. S. PACKARD, Jr. Memoirs of the Peabody Academy of Science, Volume I, Number 2. Salem, Mass., March, 1871.-This memoir contains quite full and interesting descriptions of the development of the embryos of Diplaz and Isostoma, with a few observations on Perithemis. "An interesting point in the embryology of Isostoma is the homology of the spring. Though its earliest development was not observed, it is evidently homologous with the third pair of blades comprising the unjointed ovipositor of the higher insects, and seems to be homologous with the legs and cephalic appendages." Dr. Packard also suggests that the three pairs of processes ordinarily forming the ovipositor of insects are homologous with the abdominal legs of myriapods and the spinnerets of spiders. He also concludes that the eyes and ocelli of insects do not represent limbs and that they arise on segments bearing other appendages, and, therefore, the head of insects may be considered as composed of but four segments. This memoir is illustrated by two plates and several wood-cuts.

15. Seaside Studies in Natural History; by ELIZABETH C. AGASSIZ and ALEXANDER AGASSIZ. Second edition, 1871. (James R. Osgood & Co., Boston).-This is one of the few books on Natural History which combine scientific accuracy with a popular treatment of the subject. It is, moreover, the only popular work in which many of the most interesting marine animals of our shores are described and figured. It is, therefore, gratifying to see that the work has been so well appreciated as to require a second edition. In this edition but few changes have been introduced. These are chiefly in the chapter on the distribution of marine life. A list of the wood-cuts and an explanation of the abbreviations of authors' names have been added.

V.

16. Report on the Brachiopoda obtained by the U. S. Coast Survey Expedition, in charge of L. F. De Pourtales, with a Revision of the Craniida and Discinida; by W. H. DALL.-Bulletin of the Museum of Comparative Zoology, Vol. iii, No. 1, Cambridge, Mass.-In this paper all the species dredged by Mr. Pourtales are fully described, and the synonymy of these and other species and genera is well worked out. The anatomy of several of the species is described at considerable length. Two litho graphic plates, chiefly anatomical, illustrate this paper.

17. Arrangement of the Families of Mollusks, by THEODORE GILL. Smithsonian Miscellaneous Collections, February, 1871.-In view of the wide diversity of opinion among zoologists concerning the classification of Mollusca, it is not to be expected that any scheme that can be proposed at present will be generally adopted. Yet we are constantly approximating to a true natural classification of these animals, thanks to the numerous anatomical investigations that have recently been undertaken. The author of the

present work fully acknowledges the provisional character of the arrangement which he has adopted, and anticipates many changes hereafter. In reality, some improvements made within the past year would doubtless have been adopted, had not the work been in type some six months before its actual publication. It is, nevertheless, the best index to the classification of the Mollusca that has been published hitherto. It gives in a very convenient form an arrangement in accordance with the views of many of the most reliable malacologists. It is probable that in numerous cases too many families have been admitted, or divisions of minor value have been allowed family rank. This appears to be especially true for the Nudibranchs, where the classification of Dr. Gray has been followed. But such imperfections are of comparatively small importance in view of the uses for which this "arrangement is intended. It is accompanied by a useful list of authors and an alphabetical index to the names of the classes, orders, and families.

Mr. Gill admits 27 orders and 356 families.

V.

18. Supplement to the Synopsis of the Extinct Batrachia and Reptilia of North America; by E. D. COPE (Proc. Am. Phil. Soc., March 3, 1871.)-This paper contains notices of Sauropleura remex Cope, Oestocephalus amphiuminus id., Colosteus scutellatus Newb. (Proc. Ac. N. Sc. Philad., 1856); Liodon sectorius Cope (a Mosasauroid from the N. Jersey Cretaceous); Zygorapha microglypha id., (of the family Adocida) from the New Jersey Cretaceous; Catapleura ponderosa Cope, Cretaceous of N. Jersey; the Crocodilian, Boitosaurus macrorhynchus Harlan, from the upper bed of Cretaceous Green Sand of New Jersey (the Croc. basitruncatus Owen, in Cope's Syn., p. 65, a species of Holops, on p. 231); the Dinosaur, Hadrosaurus cavatus Cope, from same locality, a species of gigantic size.

19. Animals of Sponges.-Mr. H. J. CARTER, whose researches on Sponges, confirming the observations of Prof. H. James-Clark, are briefly noticed on page 70, has an extended article on the subject in the Annals and Magazine of Natural History, for July, 1871 (IV, viii, 1), illustrated by two plates.

20. On the Homologies of some of the Cranial bones of the Reptilia, and on the systematic arrangement of the class; by E. D. COPE. (Proc. Amer. Acad., xix, 194-247.)

III. MISCELLANEOUS SCIENTIFIC INTELLIGENCE.

1. Note to the Article on a new attachment to the Lantern, on page 71. From a letter to the Editors dated, Hoboken, N. J., July 8, 1871.-I have just noticed the description of my vertical lantern which you have been kind enough to publish in your July issue, and find that through some inadvertence, a credit has been omitted which I have been careful to give on all occasions.

To Prof. J. P. Cooke of Cambridge belongs the credit of first constructing a lantern to exhibit horizontal objects by first reflecting the light from the condensers upward by a mirror and then again turning the rays to the screen by a silver speculum.

Prof. Cooke kindly showed me this apparatus in operation last summer, and in the instrument which you have described I have simply improved upon his plan with reference to the mechanical arrangement, and, by interposing the first mirror between the elements of the condenser by which I have secured an evenly illuminated and uncolored field of light upon the screen, and by finding that an ordinary glass mirror silvered on the rear surface would answer perfectly well for the final reflection.

To Prof. Cooke is likewise due the idea of thus showing the waves in a tank of water circular or elliptical.

To the experiments already mentioned I have lately added a new one of unusual beauty. By clamping a large square glass Chladni plate so that one corner covers the lantern field, and cov ering this corner inch deep with water retained by a light ring of rubber, the most beautiful patterns of crispations changing with the change of tone given by the plate can be shown on the screen. Yours, &c. HENRY MORTON.

2. Note to the Article on the application of Photography to the determination of Astronomical data; by ASAPH HALL.-Mr. David Trowbridge of Waterburgh, New York, has called my attention to the fact that Professor Bartlett of West Point, had applied the photographic method to determine the times of contact in a solar eclipse as early as 1854. Professor Bartlett's observations were published in Gould's Astronomical Journal, vol. iv, p. 33.

A. H.

3. On the Color of Fluorescent Solutions; by HENRY MORTON, Ph.D.-We have from Dr. Morton a paper for the next number of this Journal describing experiments of his which sustain the interesting conclusion that "all the familiar fluorescent solutions, such as the tincture of Turmeric, of Agaric, of Chlorophyl, and the solution of Nitrate of Uranium, emit lights of the same color of fluorescence-namely, blue, identical with that developed by acid salts of quinine.

4. Indianapolis Meeting of the American Association for the Advancement of Science, Aug. 16, 1871.-According to a circular issued by the Local Committee, the first session will be held at the Academy of Music at 10 o'clock A. M., when a reception will be extended to them by his Excellency, Conrad Baker, Governor of Indiana.

Members, and those who wish to become members, are requested. immediately upon their arrival, to register their names at the office of the Local Committee, at the State House, where they will be furnished with member's tickets, and such information as may be desired in regard to accommodations, etc. The citizens have signified their desire to extend hospitality to the members. There are likewise ample hotel accommodations, and special arrangements will be made with hotel and boarding house proprietors for reduced rates. It is therefore particularly requested that persons intending to be present, will notify the Local Secretary (Prof. E. T. Cox) by letter, as early as practicable, and when possible, state the day they will arrive.

Jahresbericht über die Fortschritte der Chemie, etc. Unter Mitwirkung von A. Laubenheimer, Al Naumann, F. Nies, F. Rose, herausgegeben von Adolph Strecker. Für 1869. Erstes Heft. Giessen, 1871.

THE

AMERICAN

JOURNAL OF SCIENCE AND ARTS.

[THIRD SERIES.]

ART. XXI.-On the Testimony of the Spectroscope to the truth of the Nebular Hypothesis; by Professor DANIEL KIRKWOOD, of Bloomington, Indiana."

IN March, 1846, the partial resolution of the great nebula in Orion was announced by Lord Rosse. In September of the following year, the late Prof. W. C. Bond, of Harvard University, stated, in confirmation of this interesting discovery, that the part of the nebula about the Trapezium "was resolved into bright points of light" by the great refractor of Cambridge. "It should be borne in mind," continued Prof. B., "that this nebula and that of Andromeda have been the last stronghold of the nebular theory; that is, the idea, first thrown out by the elder Herschel, of masses of nebulous matter in process of condensation into systems."

These grand achievements were regarded by the majority of astronomers as fatal to the claims of the nebular hypothesis. It is not to be denied, however, that this celebrated theory has more than recovered from the shock which it then received; that it has, in fact, been materially strengthened by the researches and discoveries of the last twenty years. The truth of this remark is strikingly exemplified by the revelations of the spectroscope. The man who at the middle of the nineteenth century would have been bold enough to predict the discovery of the physical constitution of the heavenly bodies, or the determination of the elements of which they are composed, would have been generally deemed a scientific enthusiast. This, however, and more than this, has been actually accomplished.

AM. JOUR SCI.-THIRD SERIES, VOL. II, No. 9.-- SEPT., 1871.

In