The authors have found that pinocytosis occurs in the tegument of C. bovis from the fourth week after infection. Electron-lucid bladders surrounded by plasma membrane were encountered in the distal cytoplasm. The pinocytosis occurred in form of micropinocytotic bladders only in the bladder tegument but not in the scolex. The bladders appeared first in the superficial part of the distal cytoplasm. During the following periods of development of the larva they were dispersed in the whole distal cytoplasm and were found even in the processes of subtegumental cells and inside these cells near the heterolysosomes.