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(July, 1921) prohibition of fishing, by steam trawlers and motor vessels of more
than 50 h.p., in certain of the shallow areas in question, and limitation of use of
other parts of the nursery grounds to April, May and June. The Sub-Committee's
recommendations were approved in September, 1922, by the International Council,
and steps were, thereupon, taken to endeavour to secure the sympathetic support
of the industry in carrying out the restrictions. On November 2nd, 1925, a letter
was sent from the Ministry of Agriculture and Fisheries to associations and federations
of the industry, inviting them to consider "by what means protection may be
given to the plaice fisheries," and stating that it had been decided to discuss "at
an International Conference, which it had been suggested might be held in the
course of the winter, the practicability of an international arrangement for the
conservation of the North Sea plaice fisheries." In the meantime, it is to be
observed that the statistics for certain recent years show a decided increase in the
figures for "small plaice," as compared with "large plaice" and "medium plaice,"
harvested from the North Sea.
Report from the Bacteriological Laboratory by Dr. Graham Forbes.
During 1925 a total of no fewer than 10,710 bacteriological and microscopical
examinations were made in the investigation of infectious, contagious and other
forms of disease.
For the carrying out of all the various bacteriological examinations made
during the year over 10,500 tubes and close on 100 plates of different culture media
were prepared by the laboratory staff. The media used included over 9,500 tubes
of blood serum for diphtheria culture work alone, and over 1,000 tubes of agar,
gelatin, blood agar, tryptagar broth, various sugars, litmus milk, etc., required
for other investigations.
Diphtheria investigations.—Special visits were made to 405 different departments
in 214 schools, and 43,017 children were inspected. From those selected for throat
and nose swabbing, a total of 7,910 serum cultures were bacteriologically examined
as compared with 6,606 during 1921, a year of unusually severe diphtheria prevalence.
Out of the 7,910 examinations, 7,012 or 88.6 per cent. proved negative, 609 or 7.7 per
cent. showed the presence of diphtheria bacilli, and in 289 or 3.7 per cent. suspicious
organisms were found. These totals are inclusive of re-examinations, and were
derived from 390 children carrying diphtheria bacilli, and 213 with suspicious
organisms.
Virulence tests.—The virulence test by means of animal inoculation was applied
in the case of the more chronic persistent carriers. In 92 cases the diphtheria
bacillus was isolated in pure culture and sent to the Clinical Research Association
for the necessary animal tests. In 68, or 74 per cent., the cultures were reported
virulent, and in 24 or 26 per cent., avirulent. These results show a higher proportion
of virulent carriers than is usually found, even in time of epidemic, e.g., in the years
1921 and 1922, when out of a total of over 400 isolated cultures, gratuitously tested
by the Wellcome Research Laboratories, 66 per cent. proved virulent and 33 per
cent. avirulent, whereas in non-epidemic periods the proportions have been found
exactly reversed.
Examination of the cerebrospinal fluid as an aid to clinical diagnosis.—During
1925, 114 specimens of fluid, obtained by lumbar puncture from 105 cases, were
sent for examination to the laboratory by the medical superintendents of poor law
hospitals—as compared with 106 specimens from 100 cases dealt with in 1924.
Though primarily undertaken to assist in the diagnosis of cerebro-spinal fever,
encephalitis lethargica, polio-encephalitis and poliomyelitis, examination of the
cerebro-spinal fluid plays an important part in the differential diagnosis also of
other conditions, which simulate and need to be distinguished from the strictly
notifiable nervous diseases. Thus the ultimate findings in the 105 cases in which