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situated as to warrant the inference that they may act as association fibers between the afferent fibers from the antennæ, optic ganglia, and ventral system and the afferent fibers. There is then a possibility of a stimulus entering the brain and passing out as a motor impulse without going into the circuit of the fibers of the mushroom bodies, or, in other words, a possibility of what may be compared to reflex action in higher animals.

It appears then that the supposition of Dujardin is well supported by the finer structure of the hexapod brain. For it is evident from the details known since the publication of Flögel's paper, that the cells composing the mushroom bodies have been very highly differentiated in some of the hexapods, and this in just those forms living the most complex lives. No such bodies are to be found in the lower forms. I have never seen them, nor any indication of them, in the Thysanura, Chilopoda,” Scolopendrella, the Pauropoda and other Myriapoda, nor in any of the Crustacea that I have thus far examined. Without doubt an application of the Golgi or methylen blue methods would reveal elements in some these forms that might be compared with the cells of the mushroom bodies; but they would probably be found not so completely differentiated from other fibers as they are in the honey bee and other Hymenoptera. It may be mentioned that one does not recognize such cells in the cray-fish and the crab as figured by Retzius and Bethe. And it scarcely need be said that no such elements are shown in Retzius' figure of the brain of Nereis.

BIBLIOGRAPHY.

Bellonci, '82. Intorno alla struttura e alle connessioni dei lobi olfattori negli artropodi superiori e nei vertebrati. Reale Accad. d. Lincei. (From Cuccati.)

Berger, '78. Untersuchungen über den Bau des Gehirns und der Retina der Arthropoden. Arb. d. Zool. Inst. Wien u. Triest., I, 173-220.

2 St.-Remy ('90) describes mushroom bodies as occuring in Scutigera, which if homologous with the mushroom bodies of Hexapoda, is in accordance with Dujardin view.

Bethe, '95. Studien über das central nerven system von Carcinus mænus nebst ein neues Verfahren der Methylenblaufixation. Arch. f. Mikr. Anat., XLIV, 579-622.

Binet, '94. Contribution à l'étude du system nerveux sousintestinal des insectes. Journ. l’Anat. et Physiol., XXX, 449– 580.

Brandt, '76. Anatomical and Morphological Researches on the Nervous System of Hymenopterous Insects. Ann. Mag. Nat. Hist., (4) XVIII, 504-6.

Cuccati, '88. Uber die Organization de Gehirns der Somomya crythrocephala. Zeit. f. wiss. Zool., XLVI, 240–69.

Diehl, '76. Die Organization des Arthropoden Gehirus. Zeit. f. wiss. Zool., XXVII, 488-517.

Leydig, '64. Vom Bau des tierischen Körpers. (From Viallanes.)

Flogel, '78. Ueber den einheitlichen Bau des Gehirns in den Verschiedenen Insekten Ordunung. Zeit. f. wiss. Zool., XXX, Supplement, 556–92.

Forel, '74. Les Fourmics de la Suisse.

Rabl-Ruckhard, '75. Studien über Insektengehirne. Reichert und Du Bois Raymond's Arch. f. Anat., 488–99.

Packard, '80. The Brain of the Locust. Second Rept. U. S. Ent. Com., pp. 223–242. Retzins, '90. Zur Kenntnis des Nervensystems der Crusta

Biol. Untersuch., N. F., I, No. 1. Retzius, '95. Zur Kenntnis des Gehirnganglion und des sensiblen Nervensystems der Polychäten. Biol. Untersuch., N. F., VII, No. 2.

Saint-Remy, '90. Contribution á l'étude du cerveau chez les Arthropodes trachéátes. Lacaze Duthiers' Arch. d. Zool. Exper. et gén. (2) V sup. 4th mém.

Dujardin, 50. Mémorie sur le système nerveux des insectes. Ann. Sci. Nat., (3) XIV, 195–206.

Viallanes, '87. Le cerveau de la Guêpe. Ann. Soc. Nat., (7) II, 5–100. Viallanes, '88. Le cerveau du criquet.

Le cerveau du criquet. Ann. Sci. Nat., (7)

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EDITOR'S TABLE. The Zoological Section of the American Association for the Advancement of Science at its meeting in Springfield, Mass. in August, 1895, adopted a series of resolutions which are printed in the volume of the Proceedings recently issued (p. 159) and which are here reproduced. They were adopted with but one pertinent objection from a distinguished member of the section. This objection was that the method of determining priority of publication recommended in the resolutions was applicable to questions of nomenclature only, which was regarded as an object of a value secondary to the determination of date of discovery of matters of fact. While the fixing of date of the latter was admitted to be of great importance, it was contended by the friends of the resolutions, that the manner proposed by them was applicable to all possible cases, and that in fact the resolutions prescribed the best method of determination of priority. The mode proposed was stated to be in accord with that customary among authors and publishers generally, and that special groups of authors could not in practice sustain rules different from them. The resolutions are as follows.

Whereas : The date of publication is a question of fact to be determined by examination, and not by an arbitrary ruling: and

Whereas : In the world at large the date of publication of books is the date at which they are printed; and

Whereas : The adoption of any other date of publication would have no practical effect for this reason, and for the following additional reasons; viz. :

First; the majority of publications are not distributed, but are sold;

Second; the distribution when it occurs may be rendered ineffective by accidents such as loss of mails, fires, etc.;

Third; distribution by individuals may be delayed or prevented by absence from home, sickness or death;

Fourth ; distribution by governments of their publications is often delayed for routine reasons ;

Fifth ; the actual date of mailing will be often impossible to ascertain with precision, owing to lack of record and irregularity in the period of transmission; and

Whereas : The determination of the date of printing will generally depend on the records of the printing office and the testimony of several persons, while the time of mailing will be known generally to but one person;

RESOLVED: First.—The section of Zoology of the American Association for the Advancement of Science recommends that the date of the completion of printing of a single issue be regarded as the date of publication ;

Second.That the Section recommends that such date be printed on the last signature of all publications, whether books periodicals or "separates.”

RESOLVED: (1) That the Section of Zoology of the A. A. As. S. is impressed with the desirability of introducing the custom of placing all publications on record at some central agency together with the date of publication. (2) That a committee be appointed to obtain the approval of these resolutions by publishing societies at home and abroad. 3 That a copy of these resolutions be transmitted to the British Assoc. Adv. Science; the Zoological Society of London ; Australasian Assoc. Adv. Science; Association Francaise; Société Zoologique de France; Versamml. der Deutscher Naturforscher, n. Aertzte; Zoologisches Gesselschaft; and the International Congress of Zoology held at Leyden.

To act as the committee above referred to, the President of the Section appointed : S. A. Forbes, Champaign, Ill. ; E. A. Birge, Madison, Wis.; W. A. Lacy, Lake Forest, Ill.; George Dimmock, Canobie Lake, N. H.

The above resolutions were adopted by very large majority vote. A proposition to regard as the date of publication, the date of receipt at the central agency of record was introduced. This was not approved, as it was evident that no private arrangement made by naturalists could supersede the customs long since current in the world of authorship.

The American Association for the Advancement of Science has a peculiar custom which it seems to us might be improved. This is the use of the term vice-president to designate the presidents or chairmen of the respective sections. This expression gives use to confusion, as these officers are not the vice-presidents of the sections, but the presidents. If the expression vice-president of section so and so is used, a president is supposed, who does not exist. To avoid conflict with the title of the president of the Association, the term chairmen might perhaps be used for the so-called vice-presidents, but actual presidents of the sections.

The decimal system of record, called the Dewey system in library catalogues, appears to the management of the Naturalist to be the best method which has yet been devised. It, therefore, follows Natural Science and La Revue Scientifique in adopting it.

RECENT LITERATURE.

The Structure of Solpugids.- That indefatigable student of the Arachnida Mr. Henry M. Bernard has presented us with a valuable account of the general structure of these little known forms. And yet while we can praise the statement of facts, as a whole, we would point out that the paper contains a number of theoretical points, which have, in our estimation, no sufficient basis.

The Galeodidæ, of which over 50 species have been described, are confined to the warm portions of both hemispheres, and though abundant in certain regions, they are comparatively rare in collections; pose sibly from the fact that they are, by popular consent, accorded most poisonous qualities. They, alone of all the Archnida, show a distinct "head ” while they also have a "thorax" divided into three segments, and these points have led many authors to look upon them as forming a transition between the Archnida and the Hexapods. They also possess stigmata in the thoracic region, a condition only paralleled in the Arachnida in certain of the mites.

In his paper Bernard takes up first the external anatomy and the interesting features here are: the interpretation of the cephalic lobes as the lateral regions of the first segment which have been changed in position with the transfer of the cheliceræ; and he further tries to find them in the cephalic lobes of embryos of other Arachnids, a view with very little in morphology to support it. The beak is interpreted as fused labium labrum, neither of these, as the name of the first might imply, being appendicular in nature. The ocular tubercle is regarded as the only remnant of the original dorsal surface of the head, the rest having been displaced by the upward and backward movement of the cephalic lobes ; and, from this, the median eyes are regarded as the more primitive, the lateral as secondarily acquired. The descriptions of the limbs, as well as of the apodematous skeleton affords little to abstract, except that the author suggests that since specialized poison organs are absent the poison may come from setal-pores on the cheliceræ; and that, at any rate, the idea of their poisonous nature should not be set aside without further experiment. As little need be said of the account of the hypodermis or of the muscular systems.

The account ef the nervous system is disappointing. Although sections were cut (cf., p. 345) no use of them appears to have been made

Trans. Linn. Socy. London, Zool. Vol. vi, pt. 4, 1896.

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