The problem of the comparative nutritive value of bread made from the various high grade white or “patents” flours and the so-called “standard” meal is of some interest. The inclusion of a considerable portion of the bran in standard bread is claimed to increase largely the nutritive value of the bread. It has been known for many years that wholemeal bread containing the bran particles was especially useful as an article of diet for persons suffering from constipation, the laxative effect being due partly to the mechanical presence of indigestible fibre, partly to the irritation of the intestinal wall by the sharp bran particles causing increased peristalsis. This effect is to some extent lost after prolonged feeding.

The literature upon the presence of various ferments in milk is extremely large and dates back through many years. Up to the beginning of 1911, however, when the experiments described in this paper were undertaken, no observer had dealt with milk uncontaminated by bacteria.

This communication contains a record of a series of experiments undertaken primarily to elucidate tbe action of complement and its fractions on a Tropin-B. typhosus system as estimated by the phagocytic index. Haemolytic experiments were also undertaken with the combined object of testing the activity of the complement-fractions and of investigating by the use of another system, certain points which arose in the course of the phagocytosis experiments. The haemolytic experiments are recorded in Part II of this communication. The term “ Tropin ” employed throughout the paper to designate the antibody in an inactivated immune serum which, in the absence of complement, is able to effect sensitisation of micro-organisms for phagocytosis, has been adopted solely for the sake of convenience and entirely without prejudice to the conception we have formed of its relation to the immune opsonin so-called, or to the general antigen-antibody reaction which, under certain conditions of experiment, involves the fixation of complement.

Neisser in 1906 claimed to have discovered an organism which, when grown on lactose-agar, threw off suddenly a new strain capable of fermenting lactose. The identity of the new strain was established by Massini (1907) by many cultural and serological tests, and from that time onwards it has been generally accepted that new bacterial strains of great permanence may arise so suddenly as to justify this type of variation being named “ Mutation.”

(1) A number of Dysentery bacilli of the mannite-fermenting type have been isolated from an English asylum.

(2) These bacilli may be divided into two sub-groups, (a) those that do, and (b) those that do not (1) ferment sorbite and (2) form indol in peptone beef broth in six days.

(3) Several attempts to infect a monkey with sorbite-fermenting strains were not successful.

(4) No Dysentery bacilli were found in an examination of a considerable number of flies infesting the surroundings of chronic and acute cases of bacillary dysentery.

My thanks are due to Dr H. de R. Morgan for kindly co-operation in part of this work, to Dr J. C. G. Ledingham for his valuable advice and assistance at all times, and to Dr W. F. Menzies for supplying the material for examination.

(1) There are two methods of examining industrial material for anthrax spores, viz. agar plate cultures and the inoculation of guinea-pigs.

(2) Though no worker has yet made a large series of examinations of equal portions of the same material by both methods simultaneously, yet the available evidence indicates that animal inoculation is superior, provided that guinea-pigs, not mice, are employed.

(3) It is better to inoculate two guinea-pigs than one, and to use the centrifuged deposit of the watery extract, though this practice may also increase the mortality from pathogenic anaerobes.

(4) The inoculation of guinea-pigs is more successful than plate cultures mainly on account of the larger quantity of watery extract usually tested, which more than counterbalances the disadvantage that some of the animals died from anaerobes before they develop anthrax.

(5) If plate cultures are employed it is essential to examine the superficial colonies after a short incubation, probably 12 to 16 hours is the most suitable.

(6) Anthrax spores have been demonstrated by the inoculation method in 21·3 % of 141 samples of industrial material, supposed to have produced anthrax in Liverpool amongst those who handled them. Of these samples 28·6 % were from hides, 22·2 % from wool, 20·6 % from hair and 7·1 % from bones. The largest proportion of infected samples came from Singapore.

(7) Anthrax spores have been demonstrated in one sample of hair “ disinfected ” with 5 % fluid of high coefficient at 100° C. and in two out of six samples of hair disinfected in Germany probably by steam at 105° C. It is practically impossible to completely sterilise certain industrial materials without seriously damaging them; yet partial disinfection should on no account be abandoned, because the perfect method has not yet been discovered.

(8) Anthrax appears to be steadily increasing among domestic animals, and consequently a larger number of agriculturalists are becoming infected. The reason for this dissemination amongst animals is still obscure.

(9) We have found B. anthracis in a sample of pea meal used for feeding cattle confined to a shippon, one of which died of anthrax. The meal was probably infected from the sack.

(10) Anthrax is preventible among men and domestic animals, and its ultimate suppression depends largely upon the certainty with which bacteriologists can demonstrate the presence or absence of bacilli in suspected industrial food, or other materials.