191

tained pigment present in the cytoplasm butnot in the, nucleus. The larger cysts for the mostpart had no epithelial lining and the contentswere in close apposition with the surrounding con-nective tissue. The pigment was very abundantand gave a blue-black appearance to the central partof the tumour. It contained no iron and was regardedas melanin by the authors, who believe that thiscase is the first on record in which melanin has beenfound in an odontome. Considered as an epithelialodontome the growth has other interesting features.The view that these tumours arise from an abnormaldevelopment of the enamel organ is supported byits structure. The authors advance convincingarguments in support of their suggestion that thegrowth may have arisen as an aberration of theenamel organ of the missing permanent incisor.Whatever its origin it is peculiar in its situation,since most tumours of this nature occur in themandible, and in the small resulting disturbance oftooth development. ____

THE EX-BABY.

THE discussion on child welfare which took placeat Westminster and was reported in THE LANCET ofJuly 17th drew attention to a gap in our organisationfor the care of the child. Antenatal and baby clinicsprovide for help and direction in regard to health upto the time of weaning, but Dame Janet Campbellshowed that the " ex-baby

" lacks systematised careuntil school life begins, when the school clinics takeup their share in preventive medicine. The good workalready done has probably been reflected in improvedconditions of children who are not subject to super-vision, but we cannot let this probability satisfy us,and the hiatus between babyhood and school age mustbe bridged. The gap in organisation has a noteworthylinguistic correlate, for Dame Janet Campbell’s useof the phrase " ex-baby " is justified by the absenceof a current word to specify the infant who is nolonger " the baby " and has not yet attained thestatus of a school child. Yet during this period arebeing laid the foundations of the individual’s characterand disposition, upon which will depend his actionsand reactions, and, to a great extent, his futurehappiness and even bodily health. There is a saying,attributed in varying forms to various people, butgenerally put into the mouth of an eminent theologian,who is credited with declaring that if he could directthe training of a child up to the age of seven he carednot a bit who trained it afterwards. Modern studyof the development of character traits, however, leadsus to attach more importance to the influence of thefamily, often unwittingly exercised, than to deliberateefforts to instruct. From these observations it is onlya step to the view of Freud that, whatever may be itsexciting cause, the foundations of a psycho-neurosis arelaid in the first five years of life. Inborn temperamentplays a part, but those neurotic reactions in the natureof fear, jealousy, hatred, and the like, which appearso irrational to the observer and yet are subjectivelyself-sufficient, are but repetitions of childish emotionalbehaviour. We are so accustomed to our loss ofmemory for the period when our own reaction modeswere being laid down that we overlook the mysteryof it. We say we were too young to remember. Butany mother can give examples of the wonderfulmemory of her ex-baby, and the conclusion seemsreasonable that we forget because we are too old toremember. According to the psycho-analytic view weforget, or repress, because the period is a time of conflictbetween primitive wishes and the growing inhibitionsagainst them. Certainly the child who has " his nose I,put out of joint " by the coming of a " little stranger " I,will probably never know if a feeling of neglect then ’,experienced was the first of a train of reactionsculminating in a general tendency to undue resent-ment at any rebuff. The only child-who is often anervous child-may never pass satisfactorily throughthe stage of dependence upon the parents, and thesuccess of Barrie’s best-known play may indicate thatthe memory of that stage of dependence still attracts

both grown-ups and those who have not long passedthrough the ex-baby phase. Few of us would easilyadmit that the happenings of that phase had anyinfluence upon our appreciation of Peter Pan. Thesespeculations may appear remote from the subjectof the provision of children’s clinics, but preventivemedicine has a task before- it in the " plague ofnerves

" that interferes with the happiness and

efficiency of so many people. If the ex-baby age isthat in which are established not only character anddisposition, but also the possibilities of later neurotictroubles, then the emotional situation of the childmust be studied in conjunction with the purelyphysical side. ____

THE TOXICITY OF ZINC.THE use of zinc as a protective coating for galvanised

pipes and cooking vessels, in cosmetics and medicinally,lends interest to the question whether this metalpossesses toxic properties. The acute reaction knownas brass-founders’ ague or spelter chills, due toexposure to vapour of the metal at high temperatnres,may be disregarded as resulting from an unusualphysiochemical state ; but even here chronic mani-festations following frequent attacks have not beendescribed. The subject has been approached in tworecent articles in both of which literature bearing onit is summarised ; but the conclusions drawn areunusually diverse. One of these articles considersthe position of workers in galvanising plants! exposedto fumes of zinc sulphate and zinc chloride ; here theauthors report widespread gastro-intestinal con-

ditions, varying from gastro-enteritis in the youngerworkers to gastric and duodenal ulcers in older men.A period of from 5 to 20 years is thought necessaryfor the production of these lesions. The experimentalwork of others is claimed in support of zinc being thecausative agent. No such train of events, however,has been described in this country; on the contrary,in one district where galvanising is the stapleindustry, gastric ulcers, although not uncommonamong domestic servants, have been noted not tooccur among the factory women.The second article referred to2 gives the evidence

for considering zinc to be universally present in animaltissues, and present in remarkably similar total con-centrations in animals of different species and inapproximately constant concentrations in differentanimals of the same species. The authors deducefrom the facts that this metal, instead of beinga poison, takes part in normal metabolism -of plantsand animals. Corn deprived of zinc becomeschlorotic ; it acts as a catalytic fertiliser for maize.Animals on a zinc-free diet do not flourish : the zinccontent of yolk of egg, milk, and spermatic fluid ishigh. An understanding of the normal occurence andr6le of zinc is needed when evaluating the effects ofabnormal amounts introduced in the course ofexposure to industrial processes. The suggestion iscertainly new that zinc promotes the efficiency ofgrowth processes. ____

THE NORMAL BLOOD COUNT.IF asked the normal number of red cells per c.mm.

in the human being, nine out of ten medical men-students or practitioners-would reply, five million.A few, perhaps, would qualify their answer by sayingthat in the female the count is lower by about 500,000.The universal acceptance of this standard is some-thing of a mystery ; but the figure, repeated in text-book after text-book, is the basis for calculatingthe colour-index. The whole subject of the normalstandards for the blood has lately been carefullyreinvestigated by E. Osgood,3 working in Portland,Oregon, and his results are worthy of close considera-tion. Taking samples from healthy male medical

1 An Occupational Disease among Zinc Workers. C. P.McCord A. Friedlander, W. E. Brown, and D. K. Minster.Archiv. Intern. Med., May 15th, 1926.

2 The Significance of Zinc in the Living Organism. K. D.Drinker and E. S. Collier, Jour. Industr. Hygiene, June, 1926.

3 Archives of Internal Medicine, May 15th, 1926.