H.—3l.

" I have searched for factors which would give an apparent decrease. Some factors possibly influencing the figure, however, would appear to operate in the reverse direction. The incidence in South Taranaki is considerably higher than in other areas, while North Taranaki is lowest, with the central area midway between." " From consideration of the classes of children examined this year, it appears probable that the actual incidence is rather lower than in 1934, and approximates very closely to that of 1933. It is at least apparent that there is no further increase in incidence." With reference to goitre in Maoris, Dr. Wyn Irwin states, — " The lower incidence of this deficiency disease in Maori children (in complete examination—all grades goitre 11 18 per cent., as compared with 2449 per cent, in pakehas) is probably not due to racial immunity. The primitive water-supplies of many goitre-free Maori settlements are adverse to the ' contaminated water ' theory, while all facts in this district go to support the belief that an inadequate supply of iodine to the thyroid gland relative to its demands is the determining factor. The racial difference in this district is due to geographic distributions and personal tastes—viz., a large proportion of the coastal population are Maoris, who eat more sea foods than pakehas with same opportunities, and especially a greater variety of these, their diets including pipis, mussels (kuku), pawa, sea-egg (kina), crayfish (kaura), and, in East Cape region, seaweed (parengo). This relationship of low-goitre endemicity to pre-pakeha marine dietary can be shown by comparing the following two groups of Maori children examined this year in this district:— " A. from 13 semi-isolated coastal settlements. "B. from 15 semi-isolated inland settlements (8 in or on the border of Urewera).

"Incidence of Goitre.

" Not only is total incidence lower in former group, but marked enlargements are entirely absent. A like comparison between groups of pakeha children would be of no value, as, besides the pakeha's different dietetic habits, few live in semiisolated coastal settlements. However, high endemicity rates for both races were observed in certain inland regions, where marine fish were difficult to obtain, and the geological formations—e.g., limestone, sandstone, or gravels—-were suggestive of a low soil iodine; examples of these have been given in several monthly reports, as well as of the absence of goitre at Morere, a subcoastal settlement with iodine-rich hot springs. Besides encouraging the more general use of iodized salt (whose table use was already common), the new seaweed food preparations were repeatedly brought to the notice of nurses, teachers, and parents." Special Classes. School Medical Officers continue to co-operate with officers of the Education and Mental Hospitals Departments in measures for the welfare of children requiring special methods of education—as the mentally backward, or those suffering from deafness or speech defect. Though there are in New Zealand no " Child Guidance Clinics " as such, a considerable amount of Child Guidance work is carried out in the ordinary duties of School Medical Officers, special cases being referred for consideration to the psychological experts associated with mental hospitals. Infectious Disease. Mild epidemics of various non-notifiable infectious diseases have occurred during the year. The work of immunization against diphtheria has been continued, Dr. Cook, Medical Officer of Health, Whangarei, immunizing some five hundred children in North Auckland; Dr. Wilson immunizing the inmates of the Papatoetoe Orphanage; and Drs. Heycock and Moir carrying out immunization of some 109 children at the Trentham School.

31

Incipient. Total, all Forms. Group. Number ; I examined. Number, j Per Cent, j Number. Per Cent. A .. .. .. .. 399 11 2-75 11 2*75 B .. .. .. .. 275 65 23-65 70 25-45