The three forms of Trypanosoma gambiense have been described so often that a few words of apology are needed before brining forward the follwing note on the subject.

Since the publication of Moore and Breinl's paper (1908) a new method of wet fixation has been introduced into the technique of protozoological research. It is generally stated that the old method of drying the blood films and fixing them afterwards in absolute alcohol, destroys the minute details of nuclear and protoplasmatic structure; that the preparations made in this way are wholly misleading and the structures do not correspond to those of the living Trypanosomes. This becomes evident when we compare the figures of Moore and Breinl and of Rosenbusch (1909), who studied Tr. lewisi with the aid of wet fixation in Flemming's liquid, with those of other authors (Prowazek (1905), Wenyon (1908) etc.) who studied the same subject. The structure of the nucleus is very dissimilar with the two methods. The big karyosome observed by the first authors cannot be found with dry fixation; then only one or more minute granules are to be seen.

During the rainy season of 1908–9 an outbreak of disease among cattle occurred over a somewhat widespread area of the Mombera district, causing considerable losses in herds owned by natives.

Owing to the courtesy of my friend, Mr W. F. Cooper, B.A., who prepared blood-films and organ smears from various wild animals shot by him in British East Africa in August, 1909, I am in a position to record three new parasites from the Jackal and Buffalo. Mr Cooper prepared the films as soon as possible after the animals were shot, using either absolute alcohol or heat for fixation. On arrival in Cambridge, the films were stained in the usual manner by Giemsa.

The development of T. lewisi in the blood of the rat is accompanied by a division of the nucleus which is more like an amitosis than a mitosis.

The division of the blepharoplast, always preceded by the division of a karyosome-like granule, might be called a promitosis (sensu: Nägler, 1909).

It is not proved that autogamy or parthenogenesis takes place in rats' blood or in cultures. The evidence brought forward by Prowazek and by Moore, Breinl and Hindle proves only the existence of chromidia; neither are Schilling's recent proofs suggestive.

Under abnormal conditions hypertrophy takes place affecting the nucleus and the blepharoplast, with subsequent formation of chromidia and final fragmentation. Similar stages found in the rat-louse have been described as sexual cells.

Considering these results in connection with previous observations of Strickland and myself, we may conclude that as yet nothing whatever indicates the occurrence of any sexual process in the life-cycle of T. levrisi, both in the vertebrate and invertebrate hosts.

At the present time Ankylostoma infection in man and disability resulting therefrom has aroused much concern. The geographical origin and present distribution of the two species of Ankylostoma known to be parasitic to man are of considerable interest, even though it be only academic. It is, therefore, probable that the following note may be worthy of publication.

In the last number of Parasitology (Vol. iii. No. 1) Mr Wenyon has taken exception to an article of mine on the Leucocytozoa, published in Science Progress, October, 1909. It has been a matter of wonder to many protozoologists as well as to myself, why Mr Wenyon did not reply to my article in Science Progress itself, and thereby appeal to the readers whom he accuses me of having misled, for he states (Parasitology, p. 65) that my “survey of the group is inaccurate and contradictory.”

The fact that no inquiry seems to have been made into a matter of some general interest, namely, the reasons which, apart from “hunger,” induce mosquitoes to bite, may serve as an excuse for presenting the preliminary results of an investigation which has had, for the time being, to be discontinued. The following observations on mosquitoes were made at the Pusa Research Institute.

The specimen of the larva of H. canicalaris was obtained from the stool of an adult man, who gave the following history:

He had been in good health and had not been conscious of any intestinal disorder. On the morning of the 28th of May he happened to look down into the pan of the closet after passing a motion and noticed that there was considerable movement taking place in the motion, which was partially formed. This movement was due to the presence of a large number of larvae, several of which crawled up the edge of the pan. He secured one and brought it to me in a bottle, and it was then alive and moving vigorously about the bottle. It maintained its vitality so long as it was in my possession, and until it was despatched to Cambridge for identification.

The collection and study of tropical insects now heing undertaken in connection with medical and other researches has resulted in the publication of two or three very useful leaflets of instructions as to how to catch and send home specimens of blood-sucking and parasitic insects. These leaflets are intended for collectors who will send home their specimens soon after they have caught them: when this is impossible, when specimens have to be carted from place to place and housed, it may be, in very unsuitable quarters, it becomes important to use only the best methods for preserving them in good condition, and the best methods can be arrived at only by combining the experience of collectors in different countries.

The following case of Intestinal Myiasis occurred in a boy about twelve years of age, in normal health, who brought to me in September 1909 what he took to be “worms” discharged with his faeces. He said he did not feel anything abnormal but saw a mass of the creatures upon and in his freshly-voided faeces. He called his mother, and she stated to me afterwards that the “worms were in a cluster like a swarm of bees,” they were crawling about the faecal mass which was loose in character, as had been the case for several days. They varied considerably in size, as did the specimens brought to me. The mass of creatures would have filled one or two tablespoons.

I Have been much interested in Professor Nuttall's paper in the April number of Parasitology (this volume, p. 113) and especially in his description of a parasite found by him in blood smears from a buffalo sent to England from British East Africa. He has named this organism Spirochaeta bovis caffris though he is evidently somewhat doubtful as to its nature. I write to say that early in 1909 I received from Captain Hadow one blood smear from a Jackson Hartebeeste which he had shot in the Bahr-El-Ghazal and on the body of which he found G. morsitans in the act of feeding. In this smear I found organisms which answered very closely to those described and figured by Professor Nuttall. They were somewhat smaller, having an average length of 16·5 μ and a breadth of 0·7 μ but presented the same appearance, stained in the same way and in some instances showed the achromatic transverse bands which he mentions. From its shape I mentally termed one variety the buffalo-horn type and I made drawings of the different forms encountered. On April 18th 1909 I sent the slide to Dr Wenyon at the London School of Tropical Medicine with a note directing his attention to these curious parasites and stating that, to me, they looked more like spirochaetes than anything else but that I was unable to classify them. Unfortunately, though my letter was safely delivered, the box containing the slide was never seen again. Dr Wenyon, however, wrote and told me that he had come across similar forms in the blood of big game which had been shot, and recorded his opinion that the forms in question were not blood parasites at all but were derived from the intestine and had been carried into the exit wound by the bullet or by discharges finding their way along the bullet track. One recognised the possibility of such an occurrence and the fallacies to which it might give rise and, on meeting Captain Hadow, I asked him if he remembered where the animal had been shot. To the best of his recollection the bullet had passed through the neck severing the gullet and it is quite possible that in the last throes stomach contents might have regurgitated through the wound of exit. The presence of very thin thread-like spirochaete forms in the film and of some bodies which suggested yeasts made me refrain from publishing any account of the case until I had more evidence regarding Dr Wenyon's hypothesis.

Dr Balfour's note raises the question whether Spirochaeta bovis caffris is a blood parasite or an organism derived from the alimentary canal owing to the entry of intestinal contents into the blood or blood stream consequent upon the effects of gunshot wounds. I must confess that this source of error did not occur to me in this case.