154 ELECTRON-MICROSCOPIC STRUCTURE OF PROTOZOA 



superficial symbiotic organisms. The micrographs by Beams and 

 colleagues show that the flagella arise from kinetosomes equally 

 spaced in concentric, incomplete circles. The basal bodies are 

 somewhat elongate (about 0-75 /x) but of conventional structure, 

 with a suggestion of a transverse septum at the level of the cell 

 membrane, above which the central flagellar fibril pair appears. 

 A rather ill-defined fibrous material interconnects the basal bodies 

 at two different levels, one at their bases and one about three- 

 fourths of their length distally. In addition, a network of fibers 

 of unknown pattern occurs in the cytoplasm between basal bodies 

 and nucleus. The origin of the calyx and its relationship, if any, 

 with the basal bodies are not explained. 



Apparently the calyx extends around the tuft of flagella for at 

 least a short distance above the recessed plate of basal bodies. 

 Here it is seen immediately below the unit cell membrane, as a 

 uniform fibrous or striated layer. Below the proximal ends of the 

 kinetosomes, it separates into bands (presumably the axostylar 

 fibers of light micrographs). Transverse sections of the cell in the 

 region of the nucleus (Fig. 62, PL XVI) show the calyx compo- 

 nents as skewed, overlapping ribbons with a finely fibrillar 

 structure resembling the axostyle wall of Tritrichomonas, Foaina, 

 and Joenia; gaps between them permit continuity of the cytoplasm 

 internal and external to the calyx. The termination of the bands 

 posteriorly is not known. The nucleus of ~Lophomonas is small, 

 spheroid, and remarkably homogeneous in the material studied. 

 Cytoplasmic structures include miscellaneous small vesicles and 

 tubules, fairly abundant Palade particles, Golgi elements, and 

 bodies identified by the authors as mitochondria, although no 

 internal membranes are evident in the published reproductions. 



The entire surface of JL. striata is deeply folded; the folds 

 generally run anteroposteriorly and are convoluted and sub- 

 divided. Clinging to the surface everywhere are longitudinally 

 oriented rods that show sufficient resemblance to bacteria that 

 identification of the characteristic striations of this species as 

 adherent microorganisms seems certain. 



L. blattarum resembles jL. striata in general morphology but 

 lacks the surface convolutions and adherent rods. Its calyx bands 

 converge to form a long axial rod posterior to the nucleus. A 

 peculiar body surrounding the nucleus and previously designated 



