The complex group of organisms with cultural and biochemical properties closely similar to the classical Cl. welchii are at present differentiated into four types according to the quality and number of the toxins they elaborate in vitro.

The present study is concerned with the specific affinities of the bacterial antigens of representative strains from these four types. The experiments confirm earlier reports concerning a wide diversity in the specificity of the somatic antigens of the classical type A strains. The bacterial antigens of the types B, C and D, however, have been shown to possess interesting similarities and affinities:

(1) The O antigen of type A (classical Cl. welchii) strains is strictly strain specific.

(2) The type B (L.D. bacillus) strains isolated in Great Britain share an identical O antigen but a strain from South Africa had a strictly specific O component.

(3) The O antigen of the type C (B. paludis) strains isolated in Great Britain is identical.

(4) The type D (B. ovitoxicus) strains exhibit wide diversity in the specificity of their O component. Thirteen strains were placed in not less than seven groups.

(5) Cross O reactions between various types is negligible or entirely absent.

(6) In addition to the heat-stable O antigen certain strains possess a heat-labile somatic component. This antigen occurs only among those types (B and D) that produce ɛ toxin but it is probably not present in all strains.

(7) Colony variants reminiscent of the typical rough forms of Gram-negative organisms are frequently encountered among strains of each type. Certain of these forms appear as stable variants and they are characterized serologically by the loss of O antigen specific for the strain.

(8) The rough forms still produce toxins characteristic of the type to which the parent culture belongs.

The question of testing for synergic action of treatments of Vibrion septique infection in mice is considered. Henderson and Gorer's data are used as the basis of the analysis.

Their six experiments are tested for heterogeneity and one experiment is found to be discrepant. This is then removed and only the remaining five used in the later working.

A x2 formula is derived for testing the significance of the evidence for synergic action. Sulphapyridine shows such interaction in effect with both antitoxin and antibacterial serum. These last two show no interaction.

The most efficient design of such experiments is then considered, and it is shown that the death rate in the single treatment tests should be kept at least as high as 90 %, and that whereas the numbers of mice assigned to the single treatment tests should be equal, that assigned to the joint treatment should be 1·5 times as great.

A graphical method for testing the significance of the results is described. These graphs also allow of an opinion being formed as to the number of mice which would be necessary to detect an interaction of given magnitude.

1. A fluid enrichment medium containing sulphite and bismuth based on Read's modification of one of Wilson & Blair's media has been devised and the claims of Read (1939) and Seal (1939) as to the value of such a medium has been confirmed.

2. A saccharose mannitol sulphite bismuth alcohol phenol red agar medium is described and has been found to allow rich growth of the true cholera vibrio and to inhibit the growth not only of B. coli and B. lactis aërogenes but of many vibrios liable to be mistaken for the true vibrio cholerae.

3. Thirty-one strains of true cholera vibrios, obtained from the National Collection, grew rapidly and profusely in the media.

4. Of twenty-five cholera-like and para-cholera strains six grew well, whilst the growth of nineteen was scanty or nil.

5. Of eleven El Tor vibrios five grew in both fluid and solid bismuth media, five grew only on the solid medium and in one no growth occurred in either medium. The El Tor colonies were much smaller than those of the epidemic cholera strains.

Ten generations of mice (with one exception) were inoculated with a partially purified toxic fraction isolated from Bact. typhi-murium, the next generation being bred each time from the survivors to the test. By this selective process a stock was produced with a substantially increased power of resistance to the toxin. For instance, in the fourth and fifth generations (combined), at which point of time the dose inoculated was stabilized at 4 mg., 36% of the mice with resistant ancestors survived inoculation compared with 12% of normal mice derived from the same original stock; in the ninth and tenth generations (combined) 64% of the resistant stock survived and only 14% of the controls. Also, those mice which failed to survive inoculation took slightly longer to die, on the average, in the resistant stock than in the normal stock.

The mice of each generation were not inoculated until about the age of 12 weeks, but to test the possibility of the transference of a passive immunity from mother to young the seventh generation was bred from without previous inoculation. The eighth generation was composed therefore of descendants of animals selected for resistance by inoculation but its own parents had not been tested. Its survival rate, 59%, was substantially greater than that of the normal stock, 17%, proving that the differences observed in previous generations were not the results of a transference of passive immunity.

Some mice of the ninth and tenth generations were inoculated with the living organism Bact. typhi-murium in place of the toxic fraction derived from it. Although these generations were relatively highly resistant to inoculation with the toxin itself they were less resistant than normal mice to the living organism.

Comparative measurements are recorded of the osmotic pressures of human and rabbit sera, both fresh and re-dissolved after drying from the frozen state (F.D. sera).

The process of drying did not alter the osmotic properties of the serum proteins.

The view that drying from the frozen state does not cause denaturation of the serum proteins is supported also by the facts that the refractive indices and the membrane potentials remained unchanged.

The toxic effects of 2-methylbutyraldehyde (isovaleraldehyde), arising from the accidental contamination of a laboratory atmosphere, are described in six out of a group of seven chemists. These were mainly tightness in the chest, irritation of the upper respiratory tract, cough, dyspnoea, marked loss of energy and weakness, dizziness, headaches, profuse perspiration, tachycardia, nausea, vomiting, diarrhoea, anorexia, somnolence, sometimes insomnia, and in one case a partial pneumothorax.

All recovered rapidly when removed from the exciting cause.

A commercial preparation of sodium hypochlorite dispersed in the form of a mist has been tested for germicidal action on bacteria suspended in the air.

The relative merits of acid, neutral and alkaline solutions have been discussed.

A maximum of efficiency dependent on dilution has been shown to exist, and experiments with water and glycerol as diluents have been performed.

The value of hypochlorous acid gas and chlorine as aerial bactericides has been tested, and experimental evidence advanced to show that while these are to some extent effective as gases, the acid, at any rate, is more lethal in solution as a mist.

Further evidence of the importance in aerial disinfection of size and evaporation rate of mist particles has been obtained.

Objections have been raised to the proprietary use of the preparation on account of the liberation of chlorine, and its high salt content, but the necessity for the presence of a certain amount of salt has been shown.

Decrease in germicidal activity of the mists when required to sterilize atomized salivas has been indicated.

The active persistence of sodium hypochlorite mists has been shown to be short.

A few notes on the use of ultra-violet light and nitration methods for combating aerial infections have been added.

It was found that the greater part of a magnesium oxide smoke inhaled by mice was retained in the upper respiratory passages.

1. The mechanical effects of morphine, heroin, codeine, dilaudid, dicodid, and eukodol upon the alimentary tract are discussed and contrasted.

2. The results of these mechanical effects upon the passage of food along the alimentary canal are discussed.

3. The constipating action of morphine is explained upon an almost purely mechanical basis.

4. From experimental evidence it is concluded that dilaudid is probably a constipating drug although this effect may not be so marked as that produced by morphine.

5. There is no experimental evidence to suggest that the administration of dicodid would ever produce constipation.

6. It is suggested that small doses of eukodol are not constipating, whereas large doses, in certain circumstances which are discussed, may produce a mild degree of constipation.

1. Meningococcal cerebrospinal meningitis in the Sudan does not materially differ in its progress and end result from the disease as found in Europe.

2. There is no racial peculiarity in response to infection or to chemotherapy.

3. There is no sex or age peculiarity in incidence. Both sexes and all ages respond to chemotherapy.

4. Sulphapyridine is superior to sulphanilamide in the shortening of invalidism and in the prevention of complications.

5. Oral administration of sulphapyridine is in the majority of cases as effective as intramuscular.

6. Dosage is related to the clinical stage of the disease, and to its duration before treatment. An initial dose of 2·5 g. sulphapyridine for adults, and 1·0—1·5 g. for children is prescribed for the serious case, with subsequent gradation of treatment to provide a maintenance dose.

7. Treatment, if it is going to give a good result, will produce a response within 24 hr. It need not be prolonged beyond 7 days. The third, fourth and seventh days of treatment are critical.