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It has been reported by hunters that certain birds become temporarily deaf. Ewald suggested that the deafness is caused by a change of intralabyrinthine pressure resulting indirectly from opening the mouth. In order to test Ewald's hypothesis, the electrical responses of the cochlea to sound stimulation were observed in the pigeon with mouth open and with mouth closed. The results show that the cochlear responses are reduced when the mouth is opened. Even slight movements of the lower jaw, such as those sometimes associated with breathing, produce a noticeable effect. The maximum effect, occurring when the mouth is wide open, varies from 8 to more than 10 db. The effect occurs for all frequencies used, from 100 to 10,000 cycles. It is suggested that the primary source of the effect is tension on the ear drum rather than a change in intralabyrinthine pressure. It may be concluded that movements of the mouth of the pigeon, even such movements as those of eating, drinking and singing, impair the hearing of the bird to a considerable extent.

THE NATURAL instinct of the newborn infant is to breathe through the nose with the mouth closed. Where this is not possible, owing to nasal obstruction, the child is in acute distress and at times cyanosed, depending for its existence on intermittent oral respiration. Possibly the insertion of an oral airway will lead to improvement in the child's condition, until an investigation of the cause of the nasal obstruction can be made. The finding of bilateral choanal atresia whilst explaining the difficulty does nothing in itself to alleviate matters so that a decision has then to be made as to how best to manage the situation. It has been usual in the past to attempt to defer curative treatment until the child is at least 6 months of age and consequently larger. Not only is this of no immediate help to the child, but we feel is unjustifiable in the

The attack behavior of captive Canada geese (Branta canadensis canadensis) in winter was studied. An analysis of responses deals mainly with the head and neck units, and utilizes evidence from several independent sources. The general nature of agonistic behavior under certain experimental conditions is described. A wild-reared goose from one flock when introduced to another integrated flock generally approaches this flock (approach may become extinguished rapidly if this animal is consistently attacked on each introduction). The integrated flock reacts characteristically to this approach, and obviously at a certain distance can discriminate between a member of its own group and an introduced stranger. As the spacial arrangement of the flock birds changes a particular group of males assembles, and from this group usually one male attacks the non-group goose. Attack behavior was arbitrarily divided into the following stages depending on the presence or absence of locomotion: approach, pre-attack, locomotory attack and post-attack. Each phase was characterized by a particular neck position, and the greatest variation in this regard occurred just prior to locomotory attack. To this extent only was there a "typical" chain of responses from flock approach to the termination of an attack. A particular combination of components (mouth open, neck tightly coiled, and head "aimed" at the opponent) appear as high threshold elements in the attack response. At times when attack probability is demonstrably low, the reciprocal of these components (i.e., mouth closed, neck extended horizontally and head directed away from the rival) frequently appears. The latter component group also appears ill-adapted for the delivery of a powerful blow by head or wings. It is suggested that complex responses consist of several behavioral components, and that any analysis of a response or between responses must incorporate all of these components. To interpret on the basis of a single component may, and often does, lead to over-simplification and possibly distortion. The coil-down neck position appears in the attacking bird and at times in the bird to be attacked. Using all components in an evaluation, the latter seems to be a protective response, and hence, there does not appear to be causal affinity between these responses. In locomotory attack, two morphologically dissimilar neck positions are recorded. The probability of their occurrence is correlated with the neck position found prior to locomotory attack. The proximity between rivals at different stages of attack was measured. Neck positions that appear to represent relatively high attack intensity proved to have relatively low mean separation distances between rivals before attack and vice versa. Proximity measures after attack do not indicate any clear trend. Wing-flapping appears frequently in locomotory attack for both captive and wild geese, whether on land or water. Flapping appears to increase the probability of contact between rivals, and may represent an increase in the intensity of the response. As clearly a high threshold element in locomotory attack, it seems to make its appearance under conditions of "high stimulus contrast".

Washington, D. C., Feb. 3,1896.To the Editor: —I have found the following method a positive cure for hiccough without the use of drugs. Immediately after the paroxysm of hiccough, close the mouth and inflate the lungs to their utmost capacity by breathing the air in through the nose; then hold the breath as long as possible; when finally compelled to expel the air from the lungs we do so and to our astonishment find that we are no longer troubled with hiccough. Once usually suffices, but it may be necessary to repeat the process the second time for the reason that during the first trial at thorough inflation of the lungs there may come a slight spasm of the glottis, when we find it necessary to quickly exhale. Immediately after this sudden exhalation take a long, full breath (mouth closed) and hold it from twenty to thirty seconds. There

In a series of 10 normal subjects, sequential scintigraphy of the salivary glands was carried out with a scintillation camera and data processing system after intravenous injection of 99m Tc pertechne-tate. Attention was focused on parotid and submandibular giand function during the first hour after injection and on the anatomic location of the oral activity. The quantitative pertechnetate function curves of the parotid and submandibular glands showed some variation between subjects, although curves of right and left glands were generally symmetric in each individual. In all subjects maximum activity was reached earlier in the submandibular gland than in the parotid gland. By comparing frontal and lateral scintiphotos made with the mouth closed and the mouth open, and by identifying the palate on the scintiphotos with the aid of a radioactive marker, it was concluded that the oral activity is located in the region of the tongue.

Subluxation [2] of the temporomandibular joint may be defined as that condition of derangement of the joint short of disIocation and unassociated with organic disease, aIthough it may occasionaIIy be due to an extra-articuIar factor. The aetioIogica1 factors of subIuxation are stiI1 IargeIy a matter of conjecture. In many instances there is no apparent causative factor; in a second group there may appear to be a questionabIe one; and in a third group a delinite injury, with continuity of compIaint from injury to diagnosis, appears to be the factor. In the second group we may pIace patients who date their troubIe from a proIonged dental treatment, a tonsillar operation or from a change in their occIusion. CIinicaIIy, the commonest first compIaint is cIicking or snapping in the region of the affected joint. The next compIaint in point of frequency is that of pain or aching about the joint. These two are folIowed by a story of locking, restricted mandibuIar movement and, very rareIy, true disIocation inthat order of frequency. We11 over haIf of the patients who come for treatment are femaIes. The average age of both femaIes and maIes in my records is twentyseven. It wouId appear that this disease is one of young females. This in itself raises an interesting point. If, as a11 writers [r,3,6,8,9] on the subject agree, the Iesion is a very common one, what happens to it as the years advance? Does it cure itseIf? Is it a serf-Iimiting disease? It is obvious that we do not know the fuI1 story of subIuxation of the temporomandibuIar joint. In those patients in whom cIicking or snapping is the onIy compIaint a very carefu1 attempt should be made to assess accurately the severity of their cIinica1 condition. UnIess the trouble is too distressing to the patients or their immediate reIatives, it would seem wise to postpone surgica1 intervention. Many of these patients may be reIieved of their compIaint by adjustment of their occIusion. They are therefore referred to their dentists. If the compIaint is of considerabIe severity, if movement is restricted or abnorma1, or if there is a story of locking, then operative treatment is indicated. Examination in this Iatter group usually reveals Iimitation of opening of the mouth; the presence of mandibuIar deviation, generaIIy to the affected side, on opening the mouth; reIative fixation of the mandibuIar head on the abnormal side; tenderness over the joint, and, rareIy, crepitus on auscultation over the joint. Radiological examination shouId incIude both joints, stereoscopic films being taken with the mouth open and with the mouth closed. It has not proved necessary to take pIanigrams on every patient, but in some cases they have proved of definite vaIue. StimuIated by Norgaard’s [IO] work we took a series of arthrograms of the temporomandibular joint in patients suffering from subIuxation. However, because of the diffrcuIty of injection, discomfort to the patient and troubIe with interpretation of the resuhing fiIms we have Iong since discontinued use of this diagnostic technic. In studying fiIms, the range of motion of the head of the mandibIe on each side is compared, as we11 as the comparative position in the joint. The most wideIy advocated sur&caI treatment of subIuxation of the temporomandibuIar joint is excision of the intra-articuIar disc [7]. WhiIe it is undoubtedIy true that the earIy resuIts are very satisfactory, very IittIe, if anything, is known of the Iate resuIts. RemovaI of the meniscus obviousIy must Iessen the

M ETHODS of measuring fish during fishery investigations have shown a marked lack of uniformity in recent years. Although standard length was used almost ugiversally in earlier studies, many investigators are now turning to total or fork length instead of standard length.1 The principal advantage of standard length is that much of the data now available on many fisheries is expressed in that dimension. Also, many investigators believe it to be more representative of the actual size of the fish than are other measurements. However, Royce (1942) indicated that total length is more representative of weight than is standard length. The present study fails to substantiate this finding. Standard length is not as easy to measure in the field as are fork or total lengths because it is difficult to determine the exact point of the body at which it is to be measured. The present study indicates that total length can be measured more accurately than standard length. Fork and total lengths also have an advantage in that they are commonly used by commercial and sport fishermen, whereas standard length is usually understood only by scientific workers. Total length is more widely used than fork length. This investigation was undertaken to determine which type of measurement can be made most accurately and which is most closely correlated with weight. Three species of fishes, Pomoxis nigro-maculatus (Le Sueur), Perca flavescens (Mitchill) and Stizostedion vitreum vitreum (Mitchill), were examined and each sample included from 98 to 150 specimens covering a wide range of sizes.2 Fish were placed flat on the measuring board so that the tip of the snout or jaw with the mouth closed was firmly against the end board. The following measurements were then recorded to the nearest millimeter for each fish

A SIMPLE WAY has been found to measure the power of the inframandibular muscles. A small platform scale was used. This is the kind of scale we stand on to weigh ourselves, and register our weight on a horizontal balancing bar. The scale was placed on a higher-than-average bench, and arranged so that the side of the platform was at the front edge of the bench, and parallel with it. A seat was arranged so that I could sit with my knees under the bench, and with my body and head erect and my mouth closed, I could bring the lower margin of the mandible flat on the platform of the scale without exerting pressure.