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identify the species with his A. erebennus in The Fishes of North and Middle America, 1896, p. 139. From Jordan's descriptions it is evi. dent that the A. prosthistius is nearer to the A. natalis than to the A. erebennus. The spines are not elongated as in the former, nor is the head long and narrowed forward, but it is short and wide; it enters the length (without caudal) 3 times and not four times. The mouth is relatively wider in the A. prosthistius, being .66 of the head-length, and not .5 of it as in A. erebennus. The inferior barbels are white in the former, while one may suppose they are black in the A. erebennus from Jordan's description. The supraoccipital spine is widely separated from the dorsal spine. In the specimens from Winslow the anal fin is relatively longer than in those from Batstow; in the former it enters the length (without caudal fin) very little over three times (3.2), while in the latter it enters from 3.5 times in one, to 3.66 in two, and 3.85 in another. The length of the anal rays is .66 of that of the head in the Winslow specimens, and .5 of the head in the Batstow speci.

The latter are of larger size.-E. D. COPE. On the Mud Minnow (Umbra pygmaea) as an air breather. - In the autumn of 1895, I tried to keep a few fishes alive in a small aquarium, viz., a glass jar holding about a gallon. This was filled with well water and some water plants placed in it which grew well. Various fish were placed in it from time to time but all without exception died in less than six hours except a Mud Minnow (Umbra pygmæa) This came to the top at frequent intervals, on each occasion emitting bubbles of air and presumably gulping more down, making considerable noise in so doing. On being placed in well aerated water six weeks or more later, this habit ceased.

The other fishes which were placed in the jar, Catfishes, Minnows, Sunfish, and Suckers would come at once to the top gasping for air, and died in an hour or two.

I have placed other of these fish— Umbra pygmæa, in well water and they acted the same way, coming to the top at frequent intervals and “ bubbling" each time.

I have never found any of these fish dead in dried up pools, though I have carefully looked for them, presumably their ability to use air for respiration saves them.-C. S. BRIM LEY.

The Peritoneal Epithelium in Amphibia.—In a recent study of the peritoneal ephithelium in Amphibia the following points were noted. The species examined were Necturus maculatus, Amblystoma punctatum, Desmognathus fusca and Diemyctylus viridescens. All the specimens of Necturus, Desmognathus and Dienyctylus were taken from January to April and none were examined after spawning. Specimens of Amblystoma were studied shortly before and immediately after ovulation, and in August and December. In all the species cilia were found only in the adult female. They occurred constantly upon the hepatic ligament, the ventral wall of the body cavity, the membranes near the mouths of the oviducts and upon the serosa of the liver. In Amblystoma cilia were also found upon the mesoarium and the membranes supporting the oviducts. Some of the adult female Necturi possessed cilia also upon the cephalic part of the dorsal wall of the body cavity. The ciliated cells occured either singly or in groups. They were most numerous near the mouths of the oviducts. It was found that the direction of the current produced by the cilia was towards and into the mouths of the oviducts. This and the fact that cilia are present upon the peritoneum of the adult female only would seem to strengthen the theory that the ova when set free in the body cavity are propelled by means of cilia into the oviducts.-ISABELLA M. GREEN.

The Penial Structure of the Sauria.-In the Proceedings of the Philadelphia Academy for August and September I have published a paper on this subject, which gives the results of an investigation into the anatomy of the hemipenes of lizards. Very little attention has been given to the subject hitherto, and our knowledge up to 1856' is thus summarized by Stannius: “A duplication or bifurcation of each organ is present in Lacerta and in Platydactylus guttatus. The copulatory organs of the Chamaeleonida are distinguished by their shortness. In various Varanidæ which have been investigated the internal cavity (external when protruded) has transverse concentric folds. A fissure interrupts these folds so that they are not complete annuli. The extremity is acuminate and expands at the base, forming a kind of glans.”

In 1870J. E. Gray describes and figure this organ of Varanus heraldicus, giving the best illustration that I know of. In 1886 Wiedersheim (Lehrbuch der Vergl Anat. Wirbelth.) describes and figures this organ in Lacerta. Besides these references I know of nothing later.

As was to have been anticipated, I have found these organs to correspond with the rest of the structure, and to furnish invaluable aids to the determination of affinities among the Sauria. Reference to them

1 Zootomie der Amphibien, p. 266. 2 Annals Magaz. Nat. Hist., 1870, VII, p. 283.

cannot be omitted henceforth in cases where the other characters render the question of affinity uncertain.

In the Sauria the male intromittent organ or bemipenis, presents much variety of structure, showing some parallels to the corresponding part in the snakes.

It is, however, rarely spinous, as is so generally the case in the Ophidia, the only spinous forms being, so far as I have examined, the American Diploglossinæ and genera allied to Cophias. The higher Sauria have the apical parts modified, as in the Ophidia, by the presence of calyculi. Such are characteristic of the Rhiptoglossa and Pachyglossa. The Nyctisaura possess the same feature. The Diploglossa, Helodermatoidea and Thecaglossa have the organ flounced, the flounces often pocketed or repand on the margin. In the Leptoglossa we have laminæ only ; in the Tiida mostly transverse, and in the Scincidæ mostly longitudinal. In various genera terminal papillæ are present. The organ may be simple or bifurcate or merely bilobate. I have not met with the case so common in the Ophidia, where the sulcus spermaticus is bifurcate and the organ undivided.

The structures of the hemipenis have a constant systematic value. As in the Ophidia, the value differs with the character, but it varies from generic to superfamily in rank.-E. D. COPE.

Food habits of Woodpeckers.-A preliminary report on the food habits of Woodpeckers has been published by F. E. L. Beal, the assistant ornithologist in the U. S. Dept. of Agriculture. The paper is based on the examinations of 679 stomachs of Woodpeckers, representing 7 species—all from the eastern United States. The results of the author's investigations are summarized as follows:

“In reviewing the results of these investigations and comparing one species with another, without losing sight of the fact that comparative good is not necessarily positive good, it appears that of 7 species considered the Downy Woodpecker is the most beneficial. This is due in part to the great number of insects it eats, and in part to the nature of its vegetable food, which is of little value to man. Three-fourths of its food consists of insects, and few of these are useful kinds.

Of grain, it eats practically none. The greatest sin we can lay at its door is the dissemination of poison ivy.”

"The Hairy Woodpecker probably ranks next to the Downy in point of usefulness. It eats fewer ants, but a relatively larger percentage of beetles and caterpillars. Its grain eating record is trifling; two stomachs taken in September and October contained corn. For fruit, it seeks the forests and swamps, where it finds wild cherries, grapes, and the berries of dogwood and Virginia Creeper. It eats fewer seeds of the poison ivy and poison sumac than the Downy."

“ The Flicker eats a smaller percentage of insects than either the Downy or the Hairy Woodpecker, but if eating ants is to be considered a virtue, then surely this bird must be exalted, for three-fourths of all the insects it eats, comprising nearly half of its whole food, are ants. It is accused of eating corn, but its stomach yielded only a little. Fruit constitutes about one fourth of its whole fare, but the bird depends upon nature and not upon man to furnish the supply."

“Judged by the results of the stomach examinations of the Downy and Hairy Woodpecker and Flicker it would be hard to find three other species of our common birds with fewer barmful qualities.

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The Ectal Relations of the Right and Left Parietal and Paroccipital Fissures.-A preliminary communication upon this subject was made by Dr. B. G. Wilder at the last session of the American Neurological Association in Philadelphia.

The following abstract presents the salient points of the paper:

“The parietal and paroccipital fissures may be either completely separated by an isthmus, or apparently continuous. When so continuous ectally there may still be an ental and concealed vadum or sballow. Disregarding the vadum on the present occasion, the ectal relations of the two fissures may be designated as either continuity or separation. That continuity occurs more frequently on the left side has been noticed by Ecker, Cunningham and the writer. Hitherto, however, statistics have included unmated cerebrums as well as mates from the same individuals. The following statement is based upon

the brums of 58 adults of both sexes and various nationalities and characters. The speaker has examined 48; the other ten have been accurately recorded by Bischoff, Dana, Jensen and Mills."

“The four possible combinations of right and left continuity and separation occurred as follows."

“I. Left continuity and right separation in 27; 46.5 per cent.
II. Right and left continuity in 22; 38 per cent.
III. Right and left separation in 8; 13.8 per cent.
IV. Left separation and right continuity in 1; 1.7 per cent."

“When five groups of persons are recognized the combinations are as follows:

A. In 8 moral and educated persons, combination I, 62.5; II, 25; III, 12.5.

B. In 23 ignorant or unknown I, 56.5; II, 34.8 ; III, 8.7.

C. In 20 insane, I, 40; II, 35; III, 20; IV, 5.
D. In four murderers, I, 0; II, 75; III, 25.
E. In three negroes, I, 33 ; II, 67.

So far as these 58 individuals are concerned, the most common combination, viz., left continuity and right separation, is decidedly the rule with the moral and educated, less frequent with the ignorant and unknown, the insane and negroes, and does not occur at all in the murderers. The only instance of the reverse combination (left separation and right continuity) is an insane Swiss woman. The only two known to be left-handed presented the more frequent combination I. (Journ. Comp. Neurol. Cincinnati, Vol. VI, 1896.)

PSYCHOLOGY.

The Nature of Feeling.-A cardinal point of dispute in carrent psychology is the nature of feeling. The division of simple feeling into pleasure and pain is generally accepted; the question that remains unsettled is the relation of these latter to sensation. Wundt, Lehmann, Marshall and other recent writers, whose views differ in important respects, agree in regarding pleasure-and-pain as a characteristic of sensation (its Gefühlston) like quality or intensity. On the other hand there are those who claim that pain (at least) is a separate species of sensation, with a distinct set of nerves and end-organs. Goldscheider at one time believed that he had discovered these pain nerves, but he has recently retracted this claim. Others, again, regard pain as an extreme form or quality of sensation common to the touch, heat and cold senses.

The problenı is somewhat complicated by the ambiguity of the word pain. In the sense of “physical pain ” (Schmerz) it may be a species of sensation ; while at the same time in the sense of " displeasure" (Unlust) it may be regarded as either an "attribute ” of sensation or a second element of consciousness. This distinction is maintained by Münsterberg and Baldwin, among others. The ordinary associations of the word pain have undoubtedly biased many writers and helped to keep alive the confusion between its two meanings.

Edited by H. C. Warren, Princeton University, Princeton, N. J. 2 Dr. Nichols in his criticism of Baldwin in the September number of this mag. azine certainly misapprehends the latter's view on this point. Cf. Mental Derelopment, pp. 483, f.

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