Page:Transactions of the Royal Society of Tropical Medicine and Hygiene, volume 1.djvu/37

 13 MEETING HELD AT 20, HANOVER SQUARE, ON WEDNESDAY, JULY 10th, 1907. Sir PATRICK M ANSON, K.C.M.G., President of the Society, in the Chair.

Dr. J. W. W, Stephens, of the Liverpool School of Tropical Medicine, showed specimens prepared by Captain S. R. Christophers, I.M.S., illustrating the Developmental Cycle of Piroplasma canis in the Tick : —
 * 1. The parasite enlarged in the gut of the tick and became a motile club-shaped body, which then left the gut and penetrated an ovum, becoming in the substance of this a " zygote."
 * 2. This zygote increased in size, and broke up into

" sporoblasts," which were found disseminated in the tissues of the larva.
 * 3. These sporoblasts further divided and accumulated as

" sporozoits" in the salivary glands of the nymph.
 * 4. Sporozoits accumulated in the salivary glands of the

adult tick. Experiment showed that the adult took in- fection and the nymph and "daughter" adult gave infection, and, corresponding to this, " sporozoits" were found in the salivary glands of the tick at both these stages. The cycle of development appeared thus to be a very simple and uncomplicated one.

The next exhibit shown by Dr. Stephens was one of the parasite discovered by Darling in Panama, Histoplasma capsulata (1906). The parasite was an intracellular one re- sembling somewhat Leishman-Donovan bodies, and existed in immense numbers in the lungs, the liver, and the spleen.

The following new helminths were also exhibited : 1. A new Bothriocephalid in man from Tasmania or Syria ; 2. A new Nematode in man from China ; and 'A. A new Ecliinorhynchus in man from British Honduras.