1^6 DESIGN IN NATURE 



PLATE LXXIII (continued) 



Figs. 20 and 21.-Ciliated zooid (Trachelophyllum apiculatum) in the extended and contracted state, n, «> Nucleus j. ™' 9°"*^*';^^^^ 

 vesicle, X200 (Wrzesniowski). These figures illustrate the vo^ver possessed by_ zooids of changing "''^ir shape by centiitu^al 

 centripetal movements ; the centrifugal movement elongating the body, the centripetal one shortening it (the Author). 



Fig. 22.— Adult ciliated animalcule {Olostoma carteri) showing band-like nucleus or endoplast (»), and stellate contractile vesicles 

 (cv, cv), X 100 (Carter). 



Figs 23 and 24.— Successive phases of sul-division of same animalcule (Fig. 22) into sporular elements (Carter). 



Figs. 25 and 26.-Urotricha lagenula s.nd farda, x .300 and 350. The latter (Fig. 26) shows spiral markings, n, Nucleus ; cv, 

 contractile vesicle (Claparede and Lachmann). 



Fig. 27.-Adiilt ciliated animalcule (Goleps hirtm), x 400. Shows pronounced longitudinal and transverse markings, x 400. 

 n, Nucleus ; cv, contractile vesicle. 



Fig. 28.— The same dividing by transverse fission, cv, Contractile vesicle. 



Figs 29 and 30.-Ciliated animalcules {Cokps fim,s and Plagiopogon coleps). n, Nucleus ; cv contractile vesicle, x 350 and 250 

 (Clap and Lach. and Pertv). Show longitudinal and transverse markings, the former most distinct. 



Figs. 31 and 32.-Siipposed trichocysts with thread-like spiral filament in the extended and retracted states (Polykrihos scUoartzii), 

 X 200 (Biitschli). 



Fig. 33.-Ciliated animalcule {Lacrymarm coluiii) illustrating spiral twisting of body, cv, Contractile vesicle, x 250 (Cohn). 



Fig. 34.-The same animalcule spherically contracted, n, Nucleus ; cv, contractile vesicle. These figures show with what facility 

 animalcules can change .heir shape by centripetal and centrifugal movements. They have complete control over every part of their 

 bodies, and their movements are voluntary (the Author). 



Fig. 35.-Ciliated adult zooid (Metaeystis truncata) .showing transverse annulation (incipient segmentation), x 400 (Cohn). 



Fig. 36.— Young zooid of same animalcule (Fig. 35) as yet devoid of transverse markings. 



Figs. 37, 38, 39, and 40.-Miicous phases of encystment and sporular mode of multiplication in Golpoda cucullus, x 200 (Stein). 



Figs. 41 and i%—Anophrys sarcophapa. Show longitudinal and transverse markings and segmentation, x 400 (Cohn). 



Fig. i3.-Trac/,elocerca phcenicopterus. Shows elongated well-formed body, with fine transverse or annular markings, x 300 

 (Cohn). Presents worm-like appearance and displays a distinct advance in organisation. 



Fig. U.—Prohoscella venniivi, x 500. Shows fin-like swimming arrangement in addition to cilia, n. Nucleus; cv, contractile 

 vesicle (W. S. Kent). 



Fig. ib.—FolUculina boltoni with flask-shaped protecting covering or lorica, x 200 (W. S. Kent). 



PLATE LXXIV 



This plate illustrates the very great variety in size and shape of Infusoria ; the presence of longitudinal, 

 transverse, and spiral markings ; the prevalence of cilia and setaB for natatory and feeding purposes ; the curved 

 spiral form of peristome ; the power of changing shape spirally or otherwise ; the double spiral arrangements 

 seen in certain immature forms, &c. 



Fig. 1.— Animalcule in an extended condition {Ghcenia teres), ciliated and free swimming, ev. Contractile vesicle, x 200 (\V. S. 

 Kent). Presents slender, worm-like appearance. 



Pig. 2.— One of the largest of the animalcules (Amphileptus gigas), ciliated, attenuate variety with contractile vesicles (cv, cv) in 

 linear series along dorsal border ; tr, trichocysts, x 100 (VVrze.sniowski). Shows well-marked longitudinal markings. 



Fig. 3.—Lembus velifer—nduU example ; cilia comparatively long, x 400 (Cohn). Shows undulating swimming membrane and 

 well-marked transverse markings. 



Fig. 4. — Normal zooid (Cyclidium glaucoma) ; setee very long and fine, n, Nucleus ; cv, contractile vesicle, x 600 (W. S. Kent). 

 Fig. 5. — Young of above (Fig. 4) as yet devoid of oral membrane. Setse as in Fig. 4. 

 Fig. 6. — Cyclidium citrellus, x 300 ; setse pronounced (Cohn). 



Fig. 7. — Adnlt a,inmalcn\e (Trachelocerca olor), cr, cu. Contractile vesicles, x 300. Shows swan-like body and neck covered with 

 fine cilia ; the body displaying spiral markings. This is one of the most elegant of the animalcules ; the neck when the animal is 

 feeding being arched and curving in all directions. 



Figs. 8, 9, and 10. — Ciliated animalcules (Metopus sigmmdes) in the extended and spiral state, x 200 (Stein). Fig. 8 .shows the 

 animalcule in the extended state covered with cilia and displaying longitudinal and oblique markings. Fig. 9 shows it extended and 

 .slightly twisted and revealing pharynx (k), nucleus (n), and contractile vesicle (cv). Fig. 10 shows it with the body spirally contorted. 

 The body is very plastic and can readily assume the various shapes indicated. On the contraction or shortening of the body, the 

 peristome with the pharynx, for the time, describes a complex spiral circuit. 



Figs. 11 and 12. — Animalcules (Dinenympha gracilis) with bodies spirally contorted ; the latter (Fig. 12) revealing a row of 

 spore-like bodies, x 666 (Leidy). The bodies in these cases are elongate-fusiform, flattened, band-like, and covered with fine cilia. 

 They are also striated longitudinally. They display great activity and power of movement. 



Fig. 13. — Zooid (Spirostomum ambiguum) with its body extended, x 150 (Stein). The body is elongated, cylindrical, and covered 

 flith cilia ; the nucleus or endoplast (n) braided and cord-like, and the contractile vesicle (cv) much expanded posteriorly. 



Fk;. 14. — A similar and larger zooid with its body spirally contorted, n, n. Braided cord-like endoplast ; cv, cv, contractile 

 vesicle extending throughout body and greatly dilated posteriorly ; or, oval aperture. This is one of the largest of the infusorial 

 type and can readily be seen with the naked eye. It possesses great mobility and displays the most graceful spirals. 



