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inclusion of the spermatozoa several hours or days may elapse before the eggs ripen and ovulation occurs. “In 1903 one interval of 2 days was recorded; in 1904, one of 4 days; in 1906, one of 6 days; in 1907, 4 days in one pond, 5 in another, and 7 in a third.”
“Egg-laying generally begins about the first of April. In two or three of the last eight years, eggs have been noted before that date. In this period, the earliest record is March 20, 1903. In 1901 they did not begin depositing eggs until after the middle of April. The egg-laying for the species may extend over a month or more. Rarely do we find fresh eggs after May 1. In 1907 our latest record for fresh eggs is April 30; our latest for fresh spermatophores in the same pond, April 27.''3
The number of eggs in a complement varies from 130 to 225. These may be deposited in one to ten bunches, two or three per female being a fair average. There is not necessarily uniformity in the size of the bunches, for one female was known to deposit two bunches, one of 140 eggs, the other of 32.
At least thirty minutes are usually consumed in depositing a normal bunch of eggs. One female in depositing a bunch of 140 eggs remained beneath the surface for over an hour. During this time she neither strove to get into a position where she could keep her nostrils out of the water, nor did she once arise to the surface for air. As in other cases, the eggs came out slowly without apparent effort or straining, sometimes but four in a minute. During deposition she was motionless, except for occasional slow movements of the tail. Immediately after deposition, however, for two or three minutes, she swayed back and forth vigorously to disengage herself, for the fresh jelly stuck to the under side of her tail and cloaca. Ten hours later another bunch of 32 eggs finished the complement.
3 Wright, A. H., “Notes on the Breeding Habits of Amblystoma punctatum,” Biological Bulletin, Vol. XIV, No. 4, April, 1908, p. 286.
NOTES AND LITERATURE
Papers from the Tortugas Laboratory of the Carnegie Institution of Washington, Vol. I, 191 pp., Vol. II, 325 pp. (Carnegie Institution of Washington Publications No. 102 and 103, 1908.)
The first collection of memoirs published in the name of the laboratory itself, from this practically tropical marine station, is highly creditable to the students who made the researches, to the director of the laboratory, Dr. A. G. Mayer, and to the great Institution which, on the financial side, has made the studies possible. Still more it is an impressive embodiment of the perception and conception that the sea is a vast, inexhaustible mine of the raw material out of which biological science is constructed; and that this material can be transformed into finished, useful product only on the ground to which it is native. Such writings drive home the truth with special force that would we really know nature we must go where nature is; we must study her in her home.
The two volumes contain nineteen papers written by fourteen naturalists, and the range of topics is almost as wide as the field of marine zoology. Yet nearly every one of these papers contains something, some of them many things, that a biologist who daily breathes the air of a large, expansive biological philosophy will want to make memorandum of for future use.
The apparel of the matter presented approaches, though does not reach, perfection. The most serious defect in the outer garments is the lack of aid to general consultation. Not only is there no alphabetical index, but the list of papers at the beginning of each volume is without page references, so one must hunt through the volume for any paper he may want to consult. The principle of the greatest good to the greatest number is against allowing scientific books, especially, to go out wanting such useful incidentals as these. The numberings and letterings of some of the illustrations are too small and indistinct to be easily read by artificial light.
Defects in some of the inner garments are more unfortunate than any in the outer. It is not necessary as one of the authors seems to think, to "investigate into” a subject. To just investigate it is enough. “Further observations are needed . .. especially with reference as to whether," etc. Why the “as to''? This sentence is bungling. But worse than bungling is the statement that “organic data function” in controlling, etc. Such expressions as this can not be let off on the plea of hasty composition, imperfect proof reading, established usage within a special field, or something of the sort. They mean hazy thinking. Literary form is not a vital thing especially to technical science. Nevertheless, considerable attention to it pays in the long run for effort in this way is promotive of clean, clear thought.
It seems to the reviewer that the word “reaction” is being overworked by some students of animal behavior. What more is there in a medusa's “fishing reaction” than in its plain fishing? And what is the gain in speaking of a bird's alighting on a stake as a “reaction''? There is a quality seemingly possessed in some degree by all minds, that tends to accept a new name for an old familiar phenomenon as in some way more explanatory of that phenomenon than the old name. Anything that encourages this tendency is not good for objective science. More, perhaps, in science than in any other domain of knowledge is there need of vigilance against bondage to words.
The subjects treated in the collection may be ranged under these heads : Cytology, normal development, regeneration, faunal zoology and animal behavior. Some of the papers fall exclusively under one head while others contain matter belonging to two or more. Such notice and comment as can be made here will be ranged under these headings.
Cytology: H. E. Jordan (“The Germinal Spot in Echinoderm Eggs”') concludes that the chromosomes in Echinaster crassispina are derived from the nucleolus, and that they arise inconstantly in different species of echinoderms from any part of the germinal vesicle that contains the chromatin material, such containers being either the nucleolus or nuclear reticulum or both, and that nothing in this research supports the theory of individuality of the chromosomes. The same author (“The Spermatogenesis in Aplopus mayeri”) finds an accessory chromosome in the phasmid studied and believes the “history of this accessory chromosome gives evidence that it at least possessed a strict morphological and probably also a physiological individuality.” One would like to know whether this statement implies that there might be
a morphological without a corresponding physiological individuality. If such an individuality is implied it is a queer kind of individuality, or would be for any other bodies than chromosomes. But chromosomes have had so many queer things attributed to them that queerness with them has almost ceased to be queer.
In a third paper (“The Relation of the Nucleolus to the Chromosomes in the primary Oöcyte of Asterias forbsii”') the same author expresses the belief that “all the hereditary elements are persistently held by the chromosomes ... and that these merely receive nutritive material from the nucleolus.” It may be granted that the figures and descriptions presented show material to be transferred from the nucleolus to the chromosomes. What the evidence is that this material is all nutritive and none of it hereditary would be extremely important. Certainly no such evidence is presented in this paper.
The fourth paper that contains cytological matter is “The Habits and Early Development of Linerges mercurius," by E. G. Conklin. The egg of this medusa presents concentric layers, the outermost of which is protoplasm nearly free from yolk. As in the eggs of various other cælenterates, cell-division, at least the first division, begins in this peripheral layer; but contrary to what has been held for some other species, the nuclei and chromosomes are here somewhat distant from the point at which the first visible changes toward division occur. There seems, consequently, no observational ground for supposing that this outer layer does not actually start up the division. This would appear to be a very significant point. Conklin gets no evidence that cell-division is ever amitotic in this species as it has been reported to be in one or two other cælenterates.
Normal Development: W. K. Brooks and B. McGlone show (“The Origin of the Lung of Ampullaria”) that in the pulmonate studied, the lung seems to be quite a different structure from that of other pulmonates and hence the conclusion is reached that “there is no reason to think that there is any ancestral connection or relation between the lung of Ampullaria and that of the pulminates.” In the paper by Conklin noted under cytology, it is shown that gastrulation in the medusa studied usually takes place by invagination, but sometimes by the immigration of a mass of endoderm cells at the vegetal pole, and the author remarks on the close relationship between the two processes. The off-hand way in which this fact is now treated, as compared with the almost frantic contention of twenty years ago that the two are fundamentally different, at least in phylogenetic significance, may well be reflected upon when our minds are turned toward theoretical biology.
Regeneration: Under this head there are two valuable papers. One (“An Experimental Study of the Rate of Regeneration in Cassiopea xamachana”) is by Chas. R. Stockard, and the other (“Some Internal Factors concerned with the Regeneration of the Chelæ of the Gulf-weed Crab”) is by Chas. Zeleny. Stockard finds no support in this research for the hypothesis that activity of the regenerating part accelerates or influences in any special way the regeneration. By cutting pieces of various shapes and sizes from the bell of the medusa, he gets the interesting result that on the animal itself the “regeneration rate is fastest from the portion from which most tissue has been removed”; and on the pieces cut away regeneration is "fastest from the part from which the least tissue has been removed." The reviewer would raise the inquiry, Does not this conclusion say essentially that the removed tissues of Cassiopea are replaced in the way necessary to effect the quickest and surest restoration of the original form of the animal regardless of the form and place of the cut?
Zeleny's researches were directed at two fundamental points : "The quantitative determination (1) of the effect of successive removal of an organ upon its power to regenerate and (2) of the character of the changes, if any, produced in the uninjured parts of the animal by such removal.” The summarized results are: (1) “When the correction for change in power of regeneration with size or age is made it is found that successive removal neither retards nor accelerates the regeneration of the right chela.” The criticism may be ventured that this conclusion is too unqualified for the number of tests made, there having been but three removals of the same chela in the same individual. As we commit ourselves more and more to quantitative methods in biology, we shall see more and more clearly, so it appears, the importance of the principle of "large numbers.” On the second object of the research the result was: “The removal and regeneration of the right chela produces no change in the growth of the uninjured left chela.”
Faunal Zoology: The titles belonging primarily under this head are: “The Pelagic Tunicata of the Gulf Stream," by W.