862 PROTOZOA [CILIATA. Tarn. 4. HALTKKIID.E. Genera. SfromWdum, Cl. & L. (Fig. XXIII. 4) ; Haltcria, Dujiird., with a supplementary girdle of springing hairs; Didiiuum, Ste in, (Fig. XXIV. 19). Fain. 5. GYKOCORID.S. . . .. Genera. Gyrocoris, Stein with an equatorial ciliary girdle spirally isposed (Fig. XXIII. 23, 21); Vroccntrum, Nitzsch, girdle annular. fia. XXIV. Ciliata -1. Ophaltnopsis sepiolie, Foett. ; a parasitic Holo trichous mouthless Ciliate from tlie liver of the Squirt, a, nuclei ; b, vacuoles (non-contractile). 2. A similar specimen treated with piero- carmine, showing a remarkably branched and twisted nucleus; a, in place of several nuclei. 3. Triehonympha ayilin, Leidy ; parasitic in the intestine of the Termites (White Ants); x 600. a, nucleus; b, granule* (food f). 4. Opalina, rannrum, Purkinje ; a Holotrichous mouthless Ciliate parasitic in the Frog s rectum ; adult ; x 100. a, a, the numerous regularly dispersed nuclei. 5. The same ; an individual in pro cess of binary fission, a, nuclei. 6. The same ; the process of fission has now reduced the individuals to a relatively small size. 7. Smallest fission- produced fragment encysted, expelled from the Frog in this state and swallowed by Tadpoles. 8. Young uninucleate individual which has emerged from the cyst within the Tadpole, and will now multiply its nuclei and grow to full si/e before in turn undergoing retrogressive 9. Anoplophrya naidon, Diij. ; a mouthless Holotrichous , ihate parasitic in the worm Nais; x 200. a, the large axial nucleus; b contractile vacuoles. 10. Anoplophrya pndifera, C. and L.; from the intestine of Uitellio. Remarkable for thu adhesion in a metamurie series of incomplete fission-products, a, nucleus. 11. Amphileptus gigas, C. and L. ; one of the Holotricha; x 100. b, contractile vacuoles ; c, tricho- tricha) ; x 80 ; showing the reticulate arrangement of the medullary pro toplasm. b, contractile vacuoles; c, the cuticle-lined pharynx. 15, 10, 17, 18. Icthi/ophthirius multifilius, Fouquet ; one of the llolotricha; x 120. Free individual and successive stages of division to form spores. a, nucleus ; b, contractile vacuoles. 19. Didinium naxittum, Mull. ; one of the Peritricha ; x 200. The pharynx is everted and has seized a Paranutcium as food, a, nucleus; b, contractile vacuole ; c, everted pharynx. 20. Euplotes charon, Mull.; one of the Hypotricha ; lateral view of the animal when using its great hypotrichous processes, x, as ambulatory organs. 21. Euplotes harpa, Stein (Hypotricha); x 150. h, mouth; x, hypotrichous processes (limbs). 22. A yctothei-ux conli- fonnis, Stein ; a Heterotrlchous Ciliate parasitic in the intestine of the Frog, a, nucleus ; b, contractile vacuole ; c, food particle ; d, anus ; c, heterotrichous band of large cilia ; J, y, mouth ; h, pluirnyx ; i, small cilia. Fam. 6. Genera. Trichodina, Ehr. ; two ciliate girdles ; body shaped as a pyramid with circular sucker-like bnse, on which is a toothed corneous ring (Fig. XXIII. 8, 9); Licnophora, Clap.; Cvdochseta, Hat. Jacks. 16 Fio. XXV. Ciliata (conjugation, Ac.). 1. Surface view of Uolotriclious
Ciliate, showing the disposition of the cilia in longitudinal rows. 2.