428 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
lives free in tlie sperm-sac ; lie finds that there are two distinct species, 
which, whilst similar in structure, differ markedly in the size of the adult, 
but principally in the size of the cytosplieres. The free form is shuttle- 
like, later on oval, and finally globular, with extremely prominent nucleus 
and nucleolus. The macronucleus, at first globular, becomes irregular, 
and finally disposes itself all through the cytosplieres, forming at first 
nodes which, later, change into new secondary nuclei equidistant from 
each other. The cytospheres group themselves around these micro- 
nuclei, which later again divide by karyokinesis, thus forming at first 
microsporogonia, then sporoblasts. These sporoblasts develope first 
into shuttle-spores. 
Mr. Eisen points out that the amitotic division of nuclei may take 
place in at least four different ways : — 
(1) Segmentation. — The nucleus divides itself in equal parts in the 
equatorial plane. 
(2) Fragmentation. — The nucleus is beaded off in various equal or 
unequal parts, not separated by regular division fields. 
(3) Badiation or Budding. — The nucleus branches out, forms nodes, 
which latter by retraction of filaments become independent nuclei. 
(4) Sporulation. — The nucleus plasma becomes by the aid of achro- 
matic filaments divided into numerous equal parts, which become set free 
and form independent nuclei. 
Tsetse Fly Disease.* — Mr. W. F. H. Blandford has a notice of 
Surgeon-Major Bruce’s preliminary report on the Tsetse fly disease in 
Zululand. For 46 years this fly has been notorious as a terrible scourge 
to live stock, and the most formidable of impediments to colonisation in 
Equatorial and South Africa. On man, nothing but temporary irritation 
is produced by the bite of this fly. Wild animals do not suffer, but 
domestic animals which have entered fly districts are seized in the 
course of a few days with fever and wasting, and almost invariably die. 
Here, as elsewhere with the progress of discovery, it has been found 
that it is not the fly which is the poisonous agent, but the microbe 
which infests it. The microbe in question appears to be a flagellated 
Infusorian about 10 to 20 p, long by 2 p wide. It is intimately allied 
to, if not identical with, Trypanosoma evansi , the cause of horse disease 
in India. These blood-parasites, after an incubation period of seven to 
twenty days, make their appearance in huge numbers in the blood of the 
patient, where they appear to worry the blood-corpuscles. The disease 
produced by the Tsetse fly belongs to the class of which malaria may 
be taken as the type. 
Independent Movements of the Chromosomes of the Malaria 
Parasite.! — M. N. Sacharoff, who had previously expressed the opinion 
that the flagella of the malaria parasites were nothing else than the 
chromatin threads extended from the cells, has recently been able to 
observe all the stages of the process and its relation to nuclear fission. 
The blood used was that of young unfledged crows taken from nests in 
malarious districts. In the earlier condition the chromatin filaments 
form an ovoid coiled up mass which, later on, divides into two portions. 
♦ Nature, liii. (1896) pp. 566-8 (2 figs.). 
t Centralbl. f. Bakteriol. u. Parasitenk., I' 8 Abt., xviii. (1895) pp. 374-80 (2 pis.). 
