646 SUMMARY OF CURRENT RESEARCHES RELATING TO 
convey fluid to it. The vacuole enlarges and then becomes emptied 
through a small efferent canal. 
The body of Codosiga passes gradually backwards into the stalk, 
which must not be regarded as a secretion, but as a chemically altered, 
hardened part of the protoplasm. Fuller details are promised. 
iEtiology of Texas Fever.* — Texas fever is an infectious disorder 
of cattle, and according to Dr. Th. Smith, is endemic between the Gulf of 
Mexico, and 37°-8° N. ; it is marked by high temperature, profound and 
rapidly occurring anaemia and very frequently haemoglobinuria. The 
chief pathological appearances found post mortem are seen in the 
spleen, which is much enlarged and soft almost to diffluence ; in the liver, 
which not only is in a condition of parenchymatous degeneration but often 
of a necrosis starting from the central veins of the lobules ; and in the 
kidneys, where a haemorrhagic oedema is conspicuous. 
On examining the fresh blood during the febrile stage many of the 
red corpuscles will be found to contain a pale mass of mobile pro- 
toplasm. Various forms of the parasite Pyrosoma bigeminum sp. n. are 
depicted by the author. Most of them are in pairs, and in the youngest 
stage are oval, more or less, while later they are distinctly pyriform. 
The pyriform bodies may lie side by side or be attached by a narrow 
bridge of protoplasm connecting their thin ends. Some of the bodies 
show corpuscles in their interior. 
The parasite was stained by heating blood-films on cover-glasses for 
1-1J hours at 110°-20° and staining for some minutes in alkaline 
methylen-blue. The preparations may be contrast-stained with eosin 
or decolorized with 1/3 per cent, acetic acid, but neither procedure is 
found to possess any particular advantage. 
In the circulation the number of corpuscles affected is rarely higher 
than 1 to 2 per cent., but in certain parts, as ascertained post mortem, 
much greater. Thus in the kidney 80 per cent, of the corpuscles are 
found to be infected ; in the liver, 30 per cent. ; in the spleen, 10 per 
cent. ; and in the heart muscle, 50 per cent. After death the intra- 
globular parasite is almost invariably round and rarely pyriform, and in 
its earliest stage, as well as in the mild or chronic form of the disease, 
the parasite is coccoid in shape. That it is intimately connected with 
the disease is obvious from the fact that healthy cattle are easily in- 
fected by subcutaneous or intravenous injection of blood from a diseased 
animal, and it is interesting to note that blood of healthy cattle from 
districts where the disease is endemic is capable of imparting the dis- 
order. The transference of the disease has been traced to ticks, Ixodes 
bovis vel Boophilus bovis by Kilborne who found that if the ticks were 
carefully removed from cattle so that the ground was not contaminated 
the disease did not break out, and further that meadows could be infected 
by scattering ripe ticks over them, even when diseased cattle were not 
present. 
The author concludes with some remarks on natural and acquired 
immunity and on cattle-diseases resembling Texas fever. 
iEtiology of Malaria.f — In describing the aetiology of malaria 
Prof. Laveran first alluded to the fact that he began to study the 
* Centralbl. f. JBakteriol. u, Parasitenk., xiii. (1893) pp. 511-27 (10 figs.), 
f Trans. Seventh Internat. Congress Hygiene, ii. (1892) pp. 10-8. 
