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7. The second and fourth grooves start from the periphery and move

toward the pole.

8. The blastomeres are more rounded and the segmentation furrows are deeper than those in most frog's eggs.

9. The development is very rapid; gastrulation begins within twelve hours, and the tadpole escapes from the egg during the second or third day.-CHARLES B. WILSON.

Figs. 1-4.

Figs. 5, 6.
Figs. 7-9.

EXPLANATION OF PLATE I.

All figures drawn with Zeiss Camera x 16 diam.

Successive stages in cleavage of living egg at intervals of 3 mins., 3 mins., 2 mins.

Stages in cleavage of second living egg.

Stages in cleavage of third living egg-intervals, 2 mins., 4 mins.

Figs. 10-15. Stages in cleavage of fourth living egg-intervals, 2, 6, 3, 4, and 5 mins.

Figs. 16-18.

Figs. 19, 20.
Fig. 21.

Figs. 22-24.

Figs. 25-27.

Stages in second cleavage of third egg.
Variations in second cleavage.
Eight-cell stage of first egg.
Stages in third cleavage of second egg.
Variations in sixteen-cell stage.

EXPLANATION OF PLATE II.

All figures drawn with Zeiss Camera.

Figs. 28-30. First cleavage under higher magnification to show rounded blastomeres.

Figs. 31, 32. Beginning of first cleavage, showing radiating wrinkles at pigmented pole.

Figs. 33-35.

Fig. 36.

Fig. 37.

Fig. 38.

Fig. 39.

Fig. 40.

Variations in wrinkles on the first furrow.
View of an egg during the fourth cleavage.
The same egg four minutes later.

Fusion and partial disappearance of the first groove.
Horizontal section of an egg during the first segmenta-
tion, taken at the level of the bottom of the furrow.
Nuclei added from the fourth section below this.
A portion of the same furrow about half way between
its bottom and the surface of the egg, more highly
magnified.

PSYCHOLOGY.'

Fear Among Children.-The term fear is applied with some ambiguity to two distinct phenomena. The sudden and unexpected advent of danger arouses the whole organism and causes an uncontrollable excitement which manifests itself in violent agitation, momentary paralysis, or other well-known signs. While the strength and duration of the emotion depends largely upon the temperament and nervous condition of the individual, it is primarily a function of the immediate stimulus, and its basis is physical rather than mental. Chronic fear, on the other hand, is determined more by the constitution of the individual than by external stimuli, and remains present after the circumstances which called it forth are removed. It occurs in every degree, from the purely normal to the extreme pathological, as exhibited in certain forms of insanity. The normal phases of this emotion are best observed in children, where repressive self-control is less liable to interfere with its open manifestation.

Prof. Alfred Binet has recently carried out such an investigation. He issued a questionary, addressed principally to school-teachers, but circulated also among parents who seemed qualified to give discriminating answers. From the nature of the case, the replies dealt generally with the more permanent form of fear (peur as distinguished from crainte). On examination of the reports, M. Binet classes the causes of fear as follows: 1. Night, darkness, solitude the sense of mystery in things-in short, what might be termed in English the quality of phantomhood. 2. Loud noises, such as thunder or the report of a gun. 3. Objects which excite repugnance or disgust: small creatures, such as rats or spiders; the sight of blood or a corpse. 4. A danger, real but not hitherto experienced by the child, whose likelihood is greatly exaggerated and which preys upon his mind; thus a child may be afraid of meeting a beggar or a drunken man, of being bitten by a dog, etc. Such a feeling is generally traceable to some story, true or false, which the child has heard. 5. The memory of a severe accident or narrow escape leads to a chronic fear of its recur

rence.

We may carry the analysis a step further than Prof. Binet. In 2 and 5, the distinctive element is a sudden nervous shock, with its after

1 Edited by H. C. Warren, Princeton University, Princeton, N. J.

2

La peur chez les enfants, Année psychologique, II, 223.

effects; in 3 and 4, the influence of the imagination predominates. Although the imagination is an important factor in 5, this class presents a distinct problem of its own, deeper rooted, which may lead the inquirer into the sphere of comparative psychology.

A point in the investigation most difficult to ascertain, was the proportion of children susceptible to fear. The answers returned varied widely, probably because the distinction between the two kinds of fear was not usually taken into account by the observers. The most reliable data seemed to indicate a general average of about 10 per cent; but the proportion appeared to be at least three times greater among girls than among boys. The question of temperament was investigated, but here too the answers varied considerably, and most diverse traits were included in the different lists; the only generalization that seemed warranted was the preponderance of fear among the gentle and timid,—which is, after all, not a point of startling novelty. On the intellectual side, where teachers are in a position to give trustworthy judgments, the figures indicate a slight excess of fear among the brighter, and a lower proportion among the more stupid than among the mediocre. Prof. Binet argues, however, that this is not due to a direct connection, but that the tendency to fear is increased by a vivid imagination, which is generally associated with greater intellectual capacity. On the other hand, there is a close connection between fear and the state of the health; and a nervous condition, whether due to a shock or otherwise, is fruitful soil for fear in children as in adults. But a further element must be reckoned with here, in the case of the child for, as he grows conscious of his failing, he loses confidence in himself, and thereby becomes still more liable to fear.

:

Aside from the concrete causes of fear already noticed, a number of factors are concerned in its development. Heredity plays a prominent part here as elsewhere. Ill-treatment is a most effective agent in fostering it, and this heading may be extended to include the many instances of misdirected efforts to train the child which are far from wilful. The pedagogical value of the study, which M. Binet brings out in a closing section, is nowhere more marked than here. Closely allied to this factor is the influence of tragic stories and mysterious tales on the child's imagination, a principle which even judicious parents are apt to forget. Finally, the force of example-the contagion of fear -is shown unmistakably by Prof. Binet's study. The younger is influenced by the older, the stronger by the weaker, the child by the teacher; if the latter show signs of fear in any crisis, the former is

almost sure to give way. This is, of course, no new discovery, but it is a fact which cannot too often be emphasized.

Fear begins to be manifested between the second and third years of age, and, until about the ninth year, the child's powers of self-control are insufficient to inhibit it. Under normal conditions, it decreases rapidly from the ninth until the twelfth year, when, apart from the influence of special conditions or circumstances, it comes well under control.-H. C. WARREN.

PROCEEDINGS OF SCIENTIFIC SOCIETIES.

American Association for the Advancement of Science.This body met at Buffalo, New York, from August 24th to 29th inclusive. The council met on the 22d, and the 29th was devoted to an excursion to Niagara. The attendance was not as large as sometimes, the number of members present being 333. The quality of the papers Only three of the sections

was said to have been in general excellent. continued in session on Friday afternoon (the 28th), viz.: the Geological, the Anthropological, and that of Social and Economic Science. The affiliated societies coöperated to a considerable extent, the Geolog. ical and Chemical Societies reading papers in the appropriate sections, and the Entomological Club suspending its meeting. Eighty-two fellows were elected. Prof. Wolcott Gibbs was elected an honorary fellow, and Mr. Horatio Hale a fellow for life. On Wednesday afternoon a symposium was held in the Geological Section in honor of the sixtieth anniversary of the appointment of Professor James Hall to the position of Director of the Geological Survey of New York.

At the opening session the association was welcomed by addresses from Mayor Jewett, and from Dr. Park, President of the Society of Natural Sciences. President E. D. Cope replied in the following

language:

"Mr. Mayor, Ladies and Gentlemen of the Local Committee and Citizens of Buffalo I utter the sentiments of the American Association for the Advancement of Science in expressing our pleasure at being once again in your beautiful city. We feel at home here, and we know that we are among friends who understand our motives and our objects. But, inasmuch as we represent the entire nation, I will give a brief outline of the objects of the Association, and the aims which it has in view. Our principal occupation is that of original scientific research, although

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