216 QUEENSLAND AGRICULTURAL JOURNAL. [1 Mar., 1898. 
DeEscrIPTION OF DIAGRAM. 
Column 1.—The free amceboid stage common to Pyrosoma and Plasmodium. 
Column 2.—The first intracorpuscular stage, also common to both organisms. 
Column 3.—The malarial amceba grown larger, and sometimes containing pigment granules. 
No corresponding stage known in Pyrosoma, which never contains pigment granules. 
Column 4.—Pyrosoma has become divided into two fresh individuals (bigeminals). Plasmodium 
shows two kinds of development: At A. (rosette development), has become 
segmented into several fresh individuals; at B. (crescent development), has become 
much enlarged, with general distribution of pigment granules. 
Column 5.—Both Pyrosoma and Plasmodium are free from containing corpuscles. The 
Plasmodium (in the rosette development) is seen to be breaking up into a number of 
free spores. N.B.—It is perhaps questionable if it is the rule for Pyrosoma to 
escape from the corpuscle, or to continue to develop in it; the eosin-staining 
particles in the crescents would seem to indicate the latter.(?) 
Column 6.—Shows Pyrosoma grown into a nucleated crescent. Plasmodium has also become a 
crescent, containing central aggregation of pigment, and showing (occasionally) traces 
of corpuscle in which it grew. Rarely two crescents are developed in a single cell 
(Manson), a condition of things somewhat resembling the bigeminal development of 
. Pyrosoma, 
Column 7.—Both kinds of crescents have become spheres. The Pyrosoma sphere is giving birth 
to free spores. 
Column 8.—Represents further developments of the Plasmodial crescent-generated sphere. At 
C. the crescent has developed abortive intracorporeal spores or, at D., thrown out 
processes which, becoming detached, represent free flagellated spores (Manson). 
CLINICAL AND PATHOLOGICAL RESEMBLANCKES. 
Malarial disease and tick fever are alike due to the presence in the blood 
of a protozoan microparasite of the Gregarine class. The organism, in both 
cases, invades the red corpuscles, which it destroys in the course of its develop- 
ment. In both diseases the microparasite remains for an indefinite time in the 
blood of infected subjects, as shown, in the case of malaria, by microscopical 
observation, and the recurrence of the fever without fresh infection; and, in 
the case of tick fever, by the persistent infectivity of the blood when injected 
into susceptible cattle. It is not known whether cattle whose blood harbours 
the parasite are subject, like malarious patients, to recurrent attacks of fever 
in the absence of all reinfection from without. 
Both diseases occur in acute, malignant, febrile forms, which are very fatal * 
and as comparatively mild and chronic apyrexial maladies. These varieties are, 
in each case, accompanied by corresponding modifications in the condition of 
the micro-organisms in the blood. The acute form (of each disease) is 
characterised by a great and rapid destruction of the red blood corpuscles, 
brought about by the direct action of the microparasites, and probably also 
by toxic substances elaborated by them. The chronic form of both maladies is — 
marked by anemia and debility. In the acute or malignant forms (of both 
diseases) the capillaries of internal organs are found to be stuffed with infected 
corpuscles, comparatively few of which are to be found in the general blood 
stream. ‘The skin and tissues, both in malaria and tick fever, frequently 
acquire a yellowish tinge due to changed colouring matter derived from the 
disintegration of the corpuscles. Hemoglobinuria is also observed from the 
same cause. Great engorgement of the spleen is a characteristic lesion of both 
maladies, and in fatal cases of each this organ is sometimes found to be quite 
disorganised, and reduced to a semifluid condition. The liver also is, in both, 
enlarged and bile-stained. Neither disease is, in nature, directly communicable 
from person to person or from bullock to bullock: neither is infectious or 
contagious in the ordinary sense. Both can, however, be transmitted by inocu- 
lating blood from diséased subjects into healthy ones of the same species. 
Other points of resemblance might doubtless be found, but enough has 
been said to show that the clinical and pathological analogies are tolerably 
close. On the other hand, it would doubtless be possible to instance particulars 
in which essential differences exist. For example, malarial diseases are known 
to be more or less controlled by quinine, and perhaps other drugs, whilst the 
bovine malady has not, so far, been found amenable to any such remedies. 
