ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
749 
observed a nucleus (5-7 /x) and also a nucleolus. Vacuoles have been 
observed, but not contractile. 
Cultivation experiments for the purpose of breeding the intestinal 
Amoeba of man have failed. 
The question of encystmont in parasitic Protozoa is always important, 
for by this means is the parasite distributed, and according to competent 
observers Amoeba coli passes through this phase. 
The facts at our present disposal render it difficult to classify the 
Amoebae coli, yet observers have attempted this, and a coarse subdivision 
into three groups has resulted : Amoebae without any pathogenic action ; 
Amoebae, the specific causes of disease ; and Amoebae which, while harm- 
less guests during health, aggravate disease when set up. 
This subdivision is rather the result of the personal equation of the 
observers than of intrinsic differences in the parasites, and the author 
concludes that the facts at our disposal do not warrant a specific classi- 
fication, much less to distinguish one group as Amoeba dysenterise. 
Cancer and Sporozoa Cell-diseases.* — This work by Dr. L. Pfeiffer 
is practically an edition de luxe of the author’s £ Die Protozoen als 
Krankheitserreger.’f 
It is issued in two volumes, the Text and the Atlas. The latter 
contains 80 photomicrographs, most of which (53) represent Sporozoa 
in muscle tissue, such as Sarcosporidia in the muscle of sheep, horse, 
and pig, Microsporidia in muscle of tortoise and frog, and Myxosporidia 
in muscle of some fish. The epithelial affections set up by Sporozoa 
receive less attention, for coccidiosis of rabbits and epithelial carcinoma 
in man are represented in 2 and 21 plates respectively, while the re- 
maining 4 show an affection of the nerves in fish ( Thymallus vulgaris ) 
— an affection termed Polyneuritis myxosporidica. 
Though much of what is dealt with is deeply interesting from a 
biological and pathological point of view it can hardly be said that the 
work bears out what is conveyed by its title, viz. researches on cancer ; 
for cancer receives less attention than some other diseases due to Sporozoa 
infection. Yet the author’s view seems clear, and we take it to be that 
there is great resemblance between many of these diseases due to animal 
parasites, and that the lower the organism is, the more readily it will 
adapt itself to its host, and therefore its pathogenic power and the de- 
struction of its host’s cells be so much the greater. The author con- 
siders that the cancer parasite belongs to that group of the Sporozoa 
called by Aime Schneider, Amoebosporidia, an organism found in cancer 
in two developmental phases ; the intracellular form which represents 
the resting cyst or resting-spore stage, and the zoospore form, when 
the parasitic germs lie free in the tissues and often infiltrate it in 
enormous numbers. 
Coccidium in Colloid Cancer. | — Dr. E. Burchardt states that he 
has found in a case of colloid cancer of the ovary, not only the intra- 
cellular forms, described by other observers, but bodies surrounded by a 
* 2 v Is., Jena, 1893, 62 figs, and 80 photomicrogr. See Central!)! f. Baliteriol. 
u. Parasitenk., xiii. (1893) pp. 618-22. f See this Journal, 1892, p. 808. 
X Virchow’s Archiv, cxxxi. (1893) No. 1 (1 p!). See Centralbl., f. Bakteriol, 
u. Parasitenk., xiv. (1893) p. 150. 
3 f 2 
