THE RELATION BETWEEN DEFECTIVE AND PROLIFIC STOCKS.

1268 that rhythmic phenomena are conditioned during the balance of equal and antagonistic opposite activities in the antagonistic "half centres "-i.e., the two efferent neurons to antagonistic muscles. It is conceivable, therefore, that, even in the absence of peripheral stimuli, the factors of fatigue and " rebound " in such centres may explain the rhythm. But Dr. Brown’s experiments have shown that with the degree of narcosis he employed both these factors He suggests that the activation were eliminated. of the half centres may be fundamentally conditioned by a stimulus equivalent to the blood Such stimuli may be stimulus in respiration. slight in degree; but it is known that stimulus is most effective when there is a close approximation to an equal and opposite activation of the half centres, so that slight changes would be So far, the reasoning is certainly in sufficient. favour of the truth of the writer’s contention. There is next to be asked, however, Of what value are the peripheral stimuli’? Do they count for nothing ? It is suggested, and here certain facts ,of evolution enter into the argument, that the spinal reflexes which excite progression are in the nature of distortions of the "beat" of the fundamental rhythm. The fundamental rhythm, being, as the experiments showed, the last to be abolished, is essentially of more primitive and fundamental origin. Originally it was possibly conditioned by circumstances closely allied to the more elemental blood stimuli with its asphyxial changes and in the mechanisms of which afferent organised channels played no part. It was the later organisation which added higher complexity. The reflex was grafted on, as it were, to the fundamental rhythm. Such an addition is represented by the normal reflexes of progression, and this now dominates, by distortion of the original beat, the original rhythm. But it remains a superimposition. It is not, in essence, the fundamental nervous We see in this paper a carefully mechanism. reasoned case against the currently accepted view, and one which must meet with a measure of acceptance until further evidence is forthcoming.

Office (Cold Spring Harbour, Long Island, New York) contain the report of the " Committee to

Study and to Report on the Best Practical Means of Cutting Off the Defective Germ Plasm in the No. 10 A describes the American Population." of scope "

the

committee’s work and No. 10B the

Legal, Legislative, and Adminstrative Aspects of

Sterilisation." The latter contains a valuable summary of the sterilisation laws which have been in 12 States of the American Union, and of the Bills introduced in other State legislatures which did not become law, but were either thrown out or vetoed by the governor or revoked by The result of all this legislative referendum. activity has been very meagre. In only three States have any sterilisation operations been performed under the statutes-namely, about 300 in Indiana, 268 in California, and7 in Connecticut. At the present time no operations of this kind are being performed as the constitutional nature of the laws is in question. But although they are dormant it would be premature to conclude that they are dead.

passed

____

"LOCALISED"

TUBERCULOSIS IN THE

PIG.

A REPORT made to the Local Government Board Dr. A. Eastwood and Dr. F. Griffith,1 which has been issued recently, gives the results of a valuable seiies of observations on the distribution of visible tuberculous lesions and of tubercle bacilli in a considerable series of pigs selected at the slaughterhouse as examples of minor degrees of pig tuberculosis. The term "localised"tuberculosis is often loosely used in meat inspection, but in the sense in which it is used in this report it signifies disease which as a result of naked-eye examination is apparently confined to the lymphatic glands in relation to the alimentary tract. It is clear that among the ordinary pigs which come to the slaughter-house tuberculosis which is actually localised in this way is much less common than tuberculosis which is more or less widely disseminated. Thus at the Brighton abattoir, from which a large part of the material was obtained, 24,144 pigs were exaTHE RELATION BETWEEN DEFECTIVE AND mined during the period of selection, of which PROLIFIC STOCKS. 209 were reported by the meat inspector to be affected by general tuberculosis, 393 had slightly THE paper by Mr. M. Greenwood, jun., and Mr. G. disseminated tuberculosis, while localised tubercuUdny Yule on the Determination of Size of Family losis was present in only 59. The pig, as the work and of the Distribution of Characters in Order of of the Roval Commission on human and animal Birth from Samples taken through Members of the is susceptible to infection tuberculosis Sibshipsis one of considerable importance in that with various showed, of mammalian type (including bacilli it impugns on statistical grounds statements made bovine and human) and with avian bacilli. By far on high statistical authority, which if true would the most common source of its natural infection is -10ive serious cause for alarm. These statements the bovine, derived from tuberculous milk or from are, first, that defective stocks are more prolific the tuberculous fiscal discharges of cattle; but avian than the normal; and, secondly, that the earlierborn members of a family are more liable to infection may also arise from ingestion of the exhibit defects than the later born. The signifi- excreta of fowls affected by the disease, while in one or two of the series here reported on the cance of the latter view rests on the fact that the decline in the average size of the family, which has I bacilli were found to be of the eugonic type, low virulence for rabbits, indicating a human indubitably taken place in recent years, means of of infection. Avian infection in the pig source that the proportion of first- and second-born to have much smaller tendency to disappears Both circumstances would thus has increased. lead to an increasing prevalence of defect. semination-when judged by the presence of nakedMr. Greenwood and Mr. Yule express their criti- eye tuberculous lesions-than bovine infection. As cisms in a mathematical form, but the principles a rule, though not invariably, when infection was on which their reasoning is based are quite due to avian bacilli the affected glands were either enlarged or only slightly so; and they coneasily intelligible to persons without mathematical not tained gritty or calcareous nodules which were training and appear obvious when pointed out. shelled out of the surrounding tissue, leaving easily Bulletins No. 10A and 10B of the Eugenics Record 1 Journal of the

January, 1914.

Royal Statistical Society,

vol.

lxxvii., Part 2,

by

1 Reports to the Local Government Board on Public Health and Medical Subjects. New Series. No. 91. Price 3s.