The histological details of the apparatus Tt. are shown in figure II as they appear viewed with a 2 inch oil immersion lens giving about 1000 diameters. While the columnar epithelial cells lining the tentacular canal Cc are not so regular as one sees in a functional organ yet they are so well defined, especially in the lower portion that the observer cannot be misled as to their identity. The nucleus is visible in about one half the cells and the nucleolus is apparent in many cases. In the upper portion the cells have lost their nuclei and are in a degenerate condition. rt is a cross-section of a muscular element which I believe is the atrophied remains of the muscular retractor of the tentacle. In my preparation, only the bony and muscular tissues have taken on the very light shade of red which characterizes rt. Since the latter is certainly not a bone, I infer it must be a muscle, and if a muscle what other function could it have had than to retract the tentacle. This muscle is visible in ten consecutive sections while the canal Ce appears in greater or less completeness in thirteen sections. The black dots of various sizes seen irregularly distributed throughout the glandular tissue ObD may possibly be nuclei as they are stained a deep red or they may be scattered nerve fibres whose connection with the ramus maxillaris on its branches I have not been able to demonstrate because the degenerate glandular tissue was so loose as to be displaced in several sections. The irregular wavy lines, I think represent cell boundaries. These are visible with an enlargement of two hundred diameters in the lower portion but can scarcely be seen with an oil immersion immediately beneath the canal. ITts is the inner tentacle sheath composed of connective tissue fibres. It is clearly seen in eighteen consecutive sections. ATts represents the outer tentacle sheath which with a low power can be seen in twenty-five consecutive sections. Thus it is observed that this tentacular apparatus is about one millimeter long lying below and external to the eye.

The tentacular canal is complete in only four sections. Figure III represents the fourth section posterior to figure II. The columar epithelium has disappeared on the dorsal side where the inner sheath enters and on one side lies close to the wall, while on the other it mingles with a loose tissue T which may be the remains of a tentacle. This tentacle is prominent in six sections, in three of which the canal is complete so that the inner sheath does not enter it. The lumen of the canal varies but slightly in size. The musculus retractor rt dwindles as we pass anterior or posterior of the section shown in figure II. The glandular tissue decreases both anterior and posterior to the median section. The portion on the ventral side persists the longest, being present in thirteen

sections. The outer tentacle sheath retains the same circumference in about thirteen sections. As soon as the canal and glandular tissue have disappeared the circumference of the outer sheath lessens in both the six posterior sections and the six sections anterior to the thirteen

Obp

Figure III. T, tentacle; mx,* branch of ramus maxillarios; other letters same as in figure II. median sections until it is only one fourth of the full size and the cells of the sheath become scattered, thus finally filling up the central area and creating a solid cord in the last two sections. It is worthy of notice that this tentacular apparatus was observed on the right hand side only in the specimen examined. In three other specimens of the same hatching, though they were several millimeters longer, no trace of the above described organ could be discerned. Kingsley has shown that no such organ exists in his specimens which were from the same lot as mine. An explanation of the occurrence of this organ in only one specimen may be found in the fact that it is an exceedingly transitory formation like the pronephros of the chick, which is present for only one day.

The second objection Kingsley makes to my observations, is that all the eye muscles are present in Amphiuma and the Sarasins say the retractor muscle of the tentacle is probably developed from the retractor bulbi. To this I answer that the Sarasins have not been able to demonstrate positively that the retractor muscle is developed from the retractor bulbi, and if it were true that the retractor muscle is developed from the retractor bulbi, I see no objection to the posterior part of the

retractor muscle functioning as a retractor bulbi after the anterior portion has undergone degeneration.

Kingsley further states that the described apparatus is not in the proper location to be compared to the tentacular organ of the Gymnophiona. In elucidating this point it is of service to compare figure I with figure IV taken from Die Anatomie der Gymnophionen von Wiedersheim.

NP

S

Figure IV. Cross section of Siphonops annulatus. NPr, naso premaxillary; Vo. vomer; M, maxillary; Atts, outer tentacle sheath; ITts, inner tentacle sheath. After Weidersheim.

It is seen that the columar-lined canal, inner tentacle sheath and outer tentacle sheath in Siphonops, have the same relation as in Amphiuma. It is further seen that the inner sheath of Siphonops is involuted ventrally to surround the tentacle while in Amphiuma a similar involution is seen on the dorsal side in Fig. III. In both genera the organ is covered merely by the skin and its subjacent tissue. The glandular tissue is not shown in Fig. IV as the section is anterior to the orbital gland. It is true the maxillary bone overhangs the apparatus in Siphonops whereas such is not the case in Amphiuma. In behalf of this contrast I quote from Cope (Bulletin of the United States National Museum, No. 34, p. 214): "There is also a very large foramen or canal passing through the o. maxillare from near its middle to the orbit, foreshadowing the canalis tentaculiferus of the cœcilia." Fig. I. is a section posterior to where the canal would enter the maxillary bone. Among the Gymnophiona there is considerable variation as to the relation of the apparatus to the maxillary bone as the following from Wiedersheim, p. 47 shows: "Sprengt man nun zum Behuf klarerer Einsicht die Deckknochen auf der betreffenden Schädelhafte volkommen ab, so wird man ein weissliches, walzenförmiges Organ gewahr, wel

ches, wei bei Caecilia, ganz vom Maxillarbein oder wei bei Epicrium und Siphonops an seiner äusseren circumferenz nur von der äusseren Haut bedeckt ist." Thus it is seen that the location of the organ in Amphiuma is very similar to its location in Gymnophiona.

A further corroboration of my views is noticed in the relation of the branches of the ramus maxillaris to the external sheath of the tentacle. According to Wiedersheim, in the Gymnophiona three branches of the maxillary nerve attend the tentacular apparatus in its course in the sub-orbital region. In Amphiuma I have found these three branches occupying the same relative position as is indicated by mx* in Fig. I. This striking similarity is seen at a glance by comparing fig. 54 in Wiedersheim's Anatomie der Gymnophionen with Fig. I. Before one can be convinced that the so-called tentacular apparatus in Amphiuma is really such I am aware my investigations must be verified by the discovery of this atrophied organ in other specimens. The importance of the discovery of such a feature is emphasized by Kingsley: "Were it true that Amphiuma possesses, either in the young or the adult, rudiments of a tentacular apparatus, the fact would prove of great value to those who would recognize in the Gymnophiona only degenerate Amphiumæ." Cope and the Sarasins have deduced considerable evidence favoring the close relationship of Amphiumide and Coeciliida, which fact renders it the more credible that a rudimentary tentacular apparatus has really been found in Amphiuma.-ALVIN DAVISON, PH. D.

PSYCHOLOGY.

Synæsthesia and Synopsia.-Until quite recently synæsthesia was regarded by psychologists generally as a purely artificial and fanci ful association, or at best as a sign of degeneracy; it has lately received considerable attention, however, and the weight of evidence goes to show that it is both natural and normal-it may even be said, a phenomenon of common occurrence.

In an exhaustive monograph on the subject, published in 1893,' Prof. Flournoy of Geneva for the first time introduced a terminology which aimed to distinguish scientifically between the different forms of synæsthesia. The most important phase is the association of visual images, or synopsia. Attention was first called to this by Fechner, in 1876. 1 Les phénomènes de la synopsie (audition colorée); by Th. Flournoy; Paris, 1893; pp. 259.

Flournoy distinguishes here between photisms, diagrams and personification. The first of these is the audition colorée of earlier writers; it consists in the natural association of a color with each particular sound, so that a spoken word appears to the hearer to be tinged with one or more hues, corresponding to its constituent vowel sounds. A diagram is a visual scheme in which some natural series of ideas (such as the months, days of the week, numbers, etc), is arranged. When a member of the series is recalled, the appropriate part of the diagram is visualized. Personification is simply the attributing of some personal characteristic, such as sex, to a number, etc.; or the association with it of a feeling of like or dislike. Flournoy reports some 350 persons as possessing synopsia in one or other of its forms, out of 2600 to whom questions were addressed, (13 per cent.); but as a large portion of his question-sheets were never returned, the real percentage may be regarded as somewhat greater.

2

In a recent paper, Miss Calkins gives the results of a personal canvass of Wellesley students in 1893 and 1894. For the former year the affirmative answers numbered 33 per cent., for the latter 60 per cent. It may be doubted whether all the latter are true cases of synopsia. Yet when due allowance is made for possible temporary associations, it must still be admitted that synopsia is by no means a rare phenomenon. Richard Hennig gives an interesting study of the diagram-forms occurring in himself and his immediate family. He is able in a number of cases to trace their origin to certain associations of early childhood, and favors the 'natural,' or experiential view of the origin of all such schemes. He strongly opposes the notion of inherited forms or photisms: Only two pair in the list given by Galton, he thinks, show any real resemblance, and these may well be accounted for by similarity of early environment. "Only the tendency to synopsia can be inherited; but here the influence of heredity is unmistakable and undoubted." The writer points out a similarity between the number-form of himself and one brother brought up under the same surroundings, while in the case of another brother, whose early life was spent in another environment, the diagram was radically different. Herr Hennig urges the usefulness of the number-form as a mnemonic aid, and cites the case of a friend, who easily memorized dates by association with the appropriate places in his number-diagram.

J. Philippe has lately investigated the synopsia of blind persons, and finds a remarkable number of cases among them, though none occurred among those who were blind from birth.

2 Synæsthesia, by Mary W. Calkins; Amer. Journal of Psychology, VII, 90–107. Ztschr. f. Psychol., X, 183-222.