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are represented by very few species in the Lesser Antilles compared with the large number that exist in other parts of the Neotropical Region both north and south of the isthmus; and almost all the species are identical with those found on the mainland.

The Pyralidæ are represented by a much greater diversity of species; but these, as in other parts of the world, are very wide ranging, most of the species being also found in Brazil and Venezuela, some being identical with forms found in the United States, whilst others range down to Chili; others again being spread throughout nearly the whole tropical zone; whilst, even of the species described as new, several are represented in the British Museum or other collections by specimens from continental localities.

Bot Flies of the Horse.-Prof. H. Garman publishes an interesting account of the habits of oviposition of Gastrophilus nasalis and G. equi. He enumerates five species of bot flies attacking the horse in America; the adults may be distinguished by the following key: 1 (6) Discoidal cell closed by a cross vein.

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4 (5) Anterior basal cell nearly or quite equal to the discoidal cell in length G. nasalis.

5 (4) Anterior basal cell markedly shorter than the discoidal cell [G. hæmorrhoidalis. G. pecorum.

6 (1) Discoidal cell not closed Concerning the habits and life history of G. equi, the most abundant species, Professor Garman writes:

This fly buzzes about horses during the hot summer days, occasionally alighting on their bodies, and when an opportunity offers, placing its eggs in the hairs on the inside of the knee, on the shoulders, and sometimes even on the mane. Its mouth-parts are in a rudimentary condition, and it can not, even if it were disposed to, do any injury to horses.

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It is probable that the grubs recently hatched from the eggs of this fly are taken into the mouths of horses on the lips or tongue. told by a gentleman who has had much experience with horses that he has on many occasions taken the eggs between the moistened palms of his hands, and in a few moments felt the young grubs wriggling about. It appears that moisture accelerates the hatching of the eggs, and it is just possible that many eggs would never hatch at all if the eggshell 7th Rept. Kentucky, Agr. Exp. Station.

was not moistened in some way. Whether this must be from the horse's tongue or lips in all cases is a question which may be considered not yet settled. Professor H. Osborn, of Iowa, is disposed to believe that the young do not hatch unless moistened by the horse's tongue; that the young grubs generally die in the eggs if left for 35 to 40 days; and that they are not commonly ready to hatch until from 10 to 12 days after the eggs are laid.

Fossil Butterflies.-Fossil butterflies are the greatest of rarities. They occur only in tertiary deposits, and out of the myriads of objects that have been exhumed from these beds in Europe and America less than twenty specimens have been found. The great body of these deposits is of course of marine origin, but at least thirty thousand specimens of insects have been recovered from those beds which are not marine. Over fifty thousand insects from the one small ancient lake of Florissant, high up in the Colorado Parks have passed through my hands, yet I have seen from them but eight butterflies. Each of these belongs to a genus distinct from the others, as is also the case with all or all but one, of the butterflies found at Radoboj, at Aix, and at Rott in the European tertiaries. With two (European) exceptions, each represents an extinct genus, and these two exceptions, Eugonia and Pontia, are genera found to-day both in Europe and America. The species, however, are all extinct.

One would hardly expect that creatures so delicate as butterflies could be preserved in a recognizable state in deposits of hardened mud and clay. Yet not only is this the case, but they are generally preserved in such fair condition that the course of the nervures and the color patterns of the wings can be determined, and even, in one case, the scales may be studied. As a rule they are so well preserved that we may feel nearly as confident concerning their affinities with those now living as if we had pinned specimens to examine; and generally speaking the older they are the better they are preserved.-S. H. Scudder in Frail Children of the Air.

Origin of European Butterflies.-Mr. W. H. Bath in discussing the effects produced by the glacial period upon the distribution and diversity of European butterflies says: As the result of his investigations Ernest Hoffmann asserts that of the 290 species of Rhopalocera inhabiting our continent at the present time, no less than 173 were originally derived from Siberia. If this was the case, and it seems very The Entomologist, XXVIII, 247.

likely to be correct, the majority of them probably immigrated westwards of the commencement of the pleistocene periods, for they must be of great antiquity; moreover it is unreasonable to suppose that many of the species could have existed also in the south of Europe, even at the climax of the glacial period. According to the same authority only 8 species have been derived from Africa, aud 39 from Asia south of Siberia. These must have immigrated into the south European province of the palearctic region after the termination of the glacial period as they belong to genera and types of tropical distribution. At the present day they occur in those countries bordering on the Mediterranean Sea.

The glacial species of butterflies--that is the most ancient forms, designated by Weismann "the original stirps "-are in many cases distinguished by their melanic and melanochroic tendencies. We thus find the forms inhabiting the more northern localities and the higher elevations on the mountains often of a darker hue, while their representatives in more southern latitudes and less elevated altitudes exhibit a brighter coloration.

North American Aphelininæ.-As the first of a technical series of bulletins to be issued by the Division of Entomology of the U. S. Department of Agriculture, Mr. L. O. Howard publishes a Revision of the Aphelininæ of North America. Regarding the biology of the group Mr. Howard writes: The insects of this subfamily are all, so far as we know, parasitic either upon the Coccidæ, Aleyrodidæ, or Aphididae. They are evidently many brooded, and issue from their hosts indifferently throughout the warmer months of the year, and through the winter on the insectary. With the Aleyrodidæ, Aphididæ, and the Diaspinæ among the Coccidæ, but one specimen apparently issues from a single host. Sufficient observations have not been made upon the early stages of the Aphelininæ. Their larvæ feed both upon the body of the scale insect and upon the eggs. They attack both sexes of the host, issuing when full-grown through circular holes, cut through the body walls, and, in the case of the Diaspine through the scale. With the scale insects of the genus Pulvinaria, the aphelinine larvæ live within the body of the female and not in the waxy egg mass which she secretes.

News.-A List of Night-flying Moths from Kentucky, is published by Prof. H. Garman in the 7th Report of the Experiment Station of that State.

An extended account of the life-history of Phryganidia californica Packard is published by Messrs. V. L. Kellogg and T. J. Jack in the Proceedings California Academy of Sciences (Ser. 2, V, 562–570.)

Prof. J. B. Smith issues as Bulletin 111 of the New Jersey Experiment Station an account of experiments with "Raupenlime" and "Dendrolene," substances useful for applying to tree trunks to keep out borers.

PSYCHOLOGY.'

American Psychological Association.-The American Psychological Association held its annual meeting this year at the University of Pennsylvania, in connection with the meetings of the scientific societies affiliated with the American Society of Naturalists. Hitherto the Psychological Association has met independently, but the feeling has been growing that the close relation between the more recent forms of psychology and the biological sciences made it eminently suitable and desirable that their representatives should be brought together. The success which has attended this first step makes it probable that the policy will be continued in future.

No official outline of the proceedings of the Psychological Associaciation is at hand, and any account written from memory will be more or less defective. Consequently the present writer must beg indulgence from those whose words he endeavors to report if he has, in any case, misrepresented them. On the whole, however, he believes he is giving a fair outline of the more important points.

At the first session, on Friday, Dec. 27th, the opening paper, on "Physiology and Psychology," was read by Prof. George S. Fullerton of the University of Pennsylvania. Two years ago, at the New York meeting of the Association, Prof. Fullerton outlined the relation in which psychology as a natural science stands to metaphysic, and concluded that psychology should adopt, as far as possible, the methods and assumptions of the other natural sciences, and should relegate the task of criticising those assumptions to a distiuct science-that of metaphysic. The paper read this year was a continuation of the same general line of thought in the investigation of the relations of psychology and physiology. Taking Foster's "Physiology" as a standard, we find, said Prof. Fullerton, that the author is absolutely unable to give any

'This department is edited by Dr. Wm. Romaine Newbold, University of Pennsylvania.

account of the functioning of the higher nervous centres without having recourse to sensations, ideas, volitions-in a word, without entering the field that properly belongs to psychology. While it may be not only right, but also necessary, for the physiologist to do this, we must not close our eyes to the fact that the mere fact of its necessity proves the imperfect condition of physiology, and tends to obscure the line dividing physiology from psychology. Prof. Fullerton claimed that the methods employed by the two sciences are distinct, and that it is important to the advancement of knowledge to recognize this distinction.

Dr. Livingston Farrand, of Columbia, submitted a scheme of physical and mental tests which will be used with the students of Columbia to determine, as far as can be done by direct experiment, their capacities in both respects at various stages of their college life. After some discussion, a motion was passed that the President be requested to appoint a committee of five to report upon the advisability of the universities represented taking concerted action in the adoption of some similar scheme.

Dr. Arthur MacDonald, of Washington, D. C., read a paper on "Some Psycho-Neural Data." He reported experiments somewhat similar to those of Dr. Farrand, made upon certain groups in the community, and apparently showing that between definite classes definite physical and mental differences are experimentally discoverable.

Prof. Lightner Witmer, of the University of Pennsylvania, introduced one of his graduate students, Mr. Oliver Cornman, who reported the results of "An Experimental Investigations of the Processes of Ideation." Mr. Cornman's method was that of giving a large number of individuals, usually children, a definite suggestion and requiring them to write for a definite period of time-usually 15 minutes-all the thoughts directly or indirectly suggested by it; he had found that in most of his subjects tne idea trains were, for a short time, largely controlled by the concomitant suggestions of the time and place, and consequently the earlier terms of each series showed a marked similarity. This soon disappeared, and the further development of the idea trains seemed dependent upon the character and previous experience of the individual. We have, therefore, in this, a convenient method of "tapping," as it were, the ideational content of the individual. Mr. Cornman pointed out further, that, to get results at all comparable with one another in the case of different bodies of subjects, the original suggestions must be given in identically the same words without explanations or further suggestions on the part of the experimenter, and, to secure this end, should always be written.

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