ADVANCE IN LOWER PLANT AND ANIMAL FORMS 173 



PLATE LXXI (continued) 



Figs. 26 and 27.— Extended and contracted phases of Heteromastix proteiformis, x 500 (J. Clark). These figures show in a striking 

 manner the centrifugal and centripetal power possessed by animalcules of changing shape and moving all their parts voluntarily and 

 at discretion (the Author). 



Fios. 28 and 29.— Malhmoiias plosslii, x 800. Show radiating awangement of fine hair-like setEe on surface of body. 

 Fig. 30. — Mallomonas fresenii with long hair-like setse, x 350. 



Figs. 31, 32, and ZS.—Asthmatos ciliaris, x 400 (Salisbury). Tliis animalcule presents a flagellum and brush-like fascicle of long 

 flexible cilia. It has a plastic body and is capable of changing shape by centripetal and centrifugal movements. At Fig. 33 the body 

 is dividing transversely to produce two individuals (the Author). 



Fig. 34. — Trichonema hirsuta, x 400 (Fromentel). 



Figs. 35 and S6.—Mitophora dubia, x 350 (Perty). Body provided with flagellum and peripheral fringe of cilia. The latter can 

 produce food currents or act as organs of locomotion. 



Fig. 37. — Stephanomonas locellus, x 400 (Fromentel). 



Fig. 38. — Geratium tripos, Miill. Normal short-armed type, x 250. 



Figs. 39 and 40. — Normal animalcule {Melodinium ubeirimiim) dividing by transverse fission, x 300 (Allnian). 



PLATE LXXII 



This plate illustrates transverse and annular markings and divisions ; radiating, concentric, and spiral arrange- 

 ments, and the plant-hke distribution of colonies of zooids. Very remarkable and beautiful as regards shape 

 and markings is the lorica or protective covering of zooids. This is, in some respects, as extraordinary as the 

 hexagonal-shaped cell of the comb of the honey-bee. It is produced by a process of secretion and is in no way 

 due to pressure. As a constructive feat it is unique in the animal kingdom both as regards the material, moulding, 

 and ornamentation. The most expert glass-blower cannot rival, far less surpass the extreme minuteness, delicacy, 

 and accuracy of the work. What explanation can be given of the fact that one of the gems of nature's architecture 

 is produced by one of the simplest animals, imless it be that the First Cause works through plant and animal 

 alike from the monad to the man ? Similar remarks apply to the marvellous constructions (shells, &c.) of the 

 Foraminifera, and stiU lower grades, witnessed in plants. 



Fig. 1. — Helmet-shaped empty lorica or, protecting covering of animalcule (Codonella galea), showing tesselated structure, 

 resembling hexagonal epithelial, liver, and pigment cells, x 200. 



Fig. 2.— Same animalcule extended beyond the orifice of its lorica. n, Nucleus ; cv, contractile vesicle (Haeckel). This animal- 

 cule bears a considerable general resemblance to certain jelly fishes (the Author). 



Fig. 3.— Empty lorica of Codonella campanella, x 200, shows exquisite symmetry and regular circular markings. 



Fig. ^.—Opalina ranarum. Body elliptical and fiattened. Shows temporarily assumed parallel disposition of the cilia, x 100 

 (W. Saville Kent). 



Figs. 5 and 7.— Examples of Arachnidium globosum with tentacles extended (Fig. 5) and reti-acted (Fig. 7). n. Nucleus ; cv, con- 

 tractile vesicle, x 1200. Body nearly spherical, oral cilia thick and tentaculiform, nucleus large and curved. The tentacles when 

 retracted assume a spiral form. 



Fig. 6.— Ventral aspect of animalcule (Halteria grandinella), x 600. Body subglobose ; springing setEe long, fine, and forming 

 central girdle ; the adoral set» at one point exhibiting spiral involution. Illustrates spiral, concentric, and radiating arrangements 

 (the Author). 



Fig. 8.— Abnormal multiple subdivision of animalcule {Didinium nasutum), x 200 (Eberhard). Body barrel-shaped, provided 

 with two wreaths of cilia— anterior and central. Shows transverse segmentation. 



Figs. 9, 10, and 11.— Natatory animalcule (nidinium nasutum) illustrating the seizure and engulf ment of a parameciitm as 

 delineated by Balbiani, x 200. Body and cilia as in Fig. 8. 



Fig. 12.— Didinium nasutum in the act of dividing by transverse fission, x 200 (Balbiani). 



Fig. 13.— Adherent zooid (Urocentrum turbo) dividing by transverse fission, x 300 (W. S. Kent). 



Fig. 14.-A(lult zooiJ (Gyrocoris oxi/ura), x 300 (Tate m). ^ Body bell-shaped, subpyriform ; claw-like tail or style; cilia forming 

 posterior marginal fringe very long and fine. Contractile vesicle large. 



Fig. 15.— Adult animalcule as figured by Eberhard, x 300. Shows well-marked spiral contour greatly resembling that of many 

 shells (the Author). 



Figs. 16 and 17.— Lateral and ventral aspects of Triehodina baltica showing denticles of adherent disc as drawn by Quennerstedt, 

 x 350. Body turban-shaped, having ring of suctorial disc toothed on both its outer and inner borders ; outer teeth recurved outwards, 

 the inner ones straight and aculeate Show two wreaths of cilia (Fig. 16), and concentric, radiating, and spiral arrangements (I-.g. 17). 



Figs. 18 and 19,— Adult expanded (Fig. 18) and contracted (Fig. 19) zooids (Zoothamnium carcini), x 200. Illustrate the power 

 possessed by zooida of changing shape by centrifugal and centripetal movements (the Author). 



Fig. 20.-Extended and contracted zooid (Vorticella cratera) as drawn by D'Udekem x 250. Body broadly campanulate, inflated, 

 and hemispherical ; peristome bodies flattened. Ciliary disc but slightly elevated ; pedicle long and stout and provided with spiral 



