214 QUEENSLAND AGRICULTURAL JouRNAL. .[1 Mar., 1898. 
These very remarkable bodies were first observed by the writer in February 
of the present year 1897, in specimens obtained from the heart’s substance of a 
cow that was killed in an advanced stage of the acute disease—possibly in the 
first stage of recovery.* Their nature was not at first at all clear, nor was their 
relation to the free amebe and to the intracellular organisms by any means 
evident. It was therefore decided, before submitting any detailed report of 
this observation, to seek the opinion of an authority of the very first eminence. 
Stained specimens were accordingly forwarded to Dr. Kleint with a request— 
as from an old pupil to a respected teacher—that he would give his opinion on 
these, to the writer, obscure points. It is hardly necessary for those who 
know Dr. Klein to say that his reply was full of “light and reading” as well 
as kindly interest and suggestion. Dr. Klein pointed out that the crescentic 
bodies are full of the young Pyrosoma—in fact, what is not nucleus is densely 
filled with these bodies, each young individual possessed of a vacuole (or perhaps 
nucleus) and a little protoplasm; that some of the crescents are so swollen 
up as to be on the point of bursting and giving birth to a new crop; that 
amongst the Pyrosoma some are considerably larger and darker stained, snd 
show a clear nucleus (or vacuole ?) ; also that some crescents are considerably 
smaller than others, and not quite crescentic yet, and not having their substance 
differentiated into young individuals. From these facts Dr. Klein leans to the 
opinion that the Pyrosoma grows up into the crescent, and that the latter 
eventually forms like a cyst endogenously a host of the Pyrosoma. 
The peculiar grouping of the crescents, before referred to, seems par- 
ticularly noteworthy in connection with the corresponding grouping together’ 
of infected corpuscles as seen in cover-glass preparations from the capillaries 
of internal organs, and seems to suggest that the clumps of crescents have had 
their origin in the clumps of Pyrosoma-infected corpuscles. 
On one occasion was discovered a’ crescent-shaped cluster of darkly- 
stained bodies (Pyrosoma ?) looking as if’ they had escaped en masse from the 
crescent envelope (vide Fig. III.), which latter is sometimes quite clearly to. be 
seen (vide Fig. V.). 
More recently some other forms which appear to be still further develop- 
ments of the crescents have been observed. The specimens were obtained 
from a cow that was killed two days after defervesence from a pretty acute 
attack of tick fever. They are well represented in Fig. V., and give the 
impression ‘that the crescents have grown into more or less irregular spheres, 
which, in many instances, have burst, scattering the spores (young Pyrosoma) 
broadcast. Intermediate stages between the crescent and sphere have. been 
observed (vide Fig. V.). The large, clear nuclear body which was so con- 
spicuous a feature in the crescent is equally apparent in the sphere, and even 
larger and more defined, but now appears to be placed centrally as a kind of 
core, round which the young Pyrosoma are clustered. In these more advanced 
stages it is also seen to have taken the gentian violet-dye to the extent that it 
has acquired a pale mauve tint. The ultimate destination of these nuclear 
bodies remains a mystery. Is it conceivable that they have some analogy with 
resting spores, and are the forms which, passing into the organism of the: 
tick, there undergo some alternative form of reproductive development ? 
The discovery of these crescentic and spheroidal bodies, representing 
further (cystic) stages in the life history of Theobald Smith’s Pyrosoma, 
supplies the piece wanting in his work, which failed only in showing how and 
where his organism was reproduced. It would seem also to bring that micro- 
organism into line with other members of the Gregarine class, in which a final 
spore-bearing cystic stage is known to be as general a characteristic as are the 
flagellated, amceboid, and cell-parasitic stages in the younger forms. It is not, 
however, intended 10 assert that this endogenous spore formation is necessarily 
the only way in which the tick fever organism multiplies, because Zoology 
* These crescents were referred to as “‘spore case-like bodies” in a progress report submitted 
to the Stock Department in March, 1897. 
+ Dr. FE. Klein, F.R.S., London. 
