ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 
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pei istomal zone, and a lively action of the contractile vacuole. During 
the process of conjugation, however, the peristome is retracted, the ves- 
tibular cavity, its cilia, and the contractile vacuoles disappear. As the 
endoplasm of the microgonidium begins to be absorbed by the macrogo- 
nidium, folds are formed by the shrivelling of the pellicle of the micro- 
gonidium, and these are the bristle-like structures described by many 
observers. The shrivelled remains of the microgonidium are cast off, 
and include some residue of the plasmic, especially ectoplasmic, material. 
Only the nuclei and the bulk of the endoplasm pass into the macrogo- 
nidium ; so that the distinction between total and partial conjugation is 
one of degree. 
Trichomonas intestinalis Leuckart.* — Herr J. Kunstler has made a 
detailed study of this Infusorian, which is a common parasite in man 
and the domestic animals. The body is pyriform, but varies in shape 
owing to the protrusion of pseudopodia. Its anterior end is furnished 
with a varying number (2-15) of flagella, inserted in a cavity or cupule 
which, according to the author, is not the mouth. The surface of the 
body is furnished with an undulating membrane whose movements give 
rise to the appearance of cilia. This membrane, characteristic of para- 
sitic Infusoria, the author believes to have been originally a pathological 
structure produced by the unfavourable conditions of parasitism. The 
protoplasm of the parasite has an alveolar structure. The author 
describes a mouth apart from the depression in which the flagella are 
placed, and also a remarkable “ hyaline style ” of unknown function 
imbedded in the protoplasm. The nucleus is oval or rounded. Repro- 
duction takes place by longitudinal division, and a process of encystation 
was also observed. 
Myxosporidia.j — Dr. Fr. Doflein describes nine new forms of 
Myxosporidia, a group of parasites in animal tissues (especially of fishes 
and arthropods), of which relatively little is known. One of his most 
interesting results is the evidence of a “multiplicative ” mode of repro- 
duction by division or budding, in addition to the “ propagative ” mode 
of reproduction by spores. As to their phylogenetic relationships, he 
agrees with Thelohan that the Myxosporidia must be regarded as der - 
vable from Rhizopods. 
* Bull. Scient. France et Belgique, xxxi. (1898) pp. 185-231 (2 pis. and 28 figs.). 
f Zool. Jahrb., xi. (1898) pp. 281-350 (7 pis. and 20 figs.). 
