. A manual of zoology. Zoology. 218 PliOTOZOA. and serve to fix the capsule, while the aniceboid germ creeps out and penetrates the tissues of the host. Experiment shows that fishes are infected through the alimentary canal. The Myxosporida frequently cause serious epidemics in fish. This was noticeably the case with the fish in the aquaria at the Chicago exposition. Myxoholus, Myxidium. Invertebrates may also be infected, the celebrated p6brine of the silkworm being caused by Nosema (Qlugea) hombycis. Order V. Sarcosporida. The Sarcos2)orida (fig. 150)—also called Rainey's or Miescher's corpu
. A manual of zoology. Zoology. 218 PliOTOZOA. and serve to fix the capsule, while the aniceboid germ creeps out and penetrates the tissues of the host. Experiment shows that fishes are infected through the alimentary canal. The Myxosporida frequently cause serious epidemics in fish. This was noticeably the case with the fish in the aquaria at the Chicago exposition. Myxoholus, Myxidium. Invertebrates may also be infected, the celebrated p6brine of the silkworm being caused by Nosema (Qlugea) hombycis. Order V. Sarcosporida. The Sarcos2)orida (fig. 150)—also called Rainey's or Miescher's corpuscles—occur in the voluntary muscles of vertebrates,esi^ecially mammals. They are oval cysts lying in sar- colemma sacs between the fibrilla;. They have a cyst, the wall of which is radially striped, and inside this, ii^ the rij^e condition, are spores, imbedded in a stroma, each spore con- taining numerous renif orm or falciform sporo- zoites. Sarcoojstis miescheriana in muscles of pig; S. iiuiris in the mouse; ;S'. Undemanni rare in human muscle. Summary of Important Facts. 1. The Protozoa are unicellular organisms without tnie organs or true tissues. 3. All vital processes are accomjilished by the protoplasm (sarcode), digestion directly Ijy its substance, locomotion and the taking of food by means of protoplasmic processes (jiseudopodia) or bv appendages (cilia and flagella). 3. Excretion takes place by special accumulations of fluid, the contractile vacuoles. •4. Reproduction is by budding or by fission. Conjugation has been witnessed in many, and possibly occurs in all. True con- jugation is a process of fertilization (caryogamy), in contrast to fusion of plasma (plasmogamy). 5. Protozoa are aquatic, a fcAv living in moist earth; they can only exist in dry air in the e:\cysted condition, surrounded by a capsule which prevents desiccation. <;. Since encysted Protozoa are easily carried by the wind, the occurrence of these animals in water which originally containe
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