The Hegnum Protisticum. clxiii 



oxygen, and the power of supporting life upon inorganic matters, are, 

 perhaps, the two points to Avhich we shoukl next look, though both of 

 them would fail us in the case of the Fungi. The presence of chlorophyll 

 in very great abundance in the parenchyma of an organism points, though 

 less certainly, than any of the three characters already specified, to the 

 vegetable character of an organism. Stentor, however, among Infusoria, 

 Hydra among Coelenterata, Vortex amongst the Turbellarian, and Bo- 

 nellia amongst Gephyrean Worms, are said, though not in all cases upon 

 the evidence of the spectroscope, to possess this chemical substance as an 

 essential ingredient of their parenchyma irrespective of any which may 

 be ingested with their aliment. An organism which should be seen to 

 envelope alimentary substances within its own parenchyma would be, in 

 almost any case, rightly considered an animal ; but this test would fail 

 with the ento-parasitic foi-ms of either kingdom which live by the ab- 

 sorption of the soluble nutriment in which they live immersed at all 

 points of their exterior ; and would further be held by most naturalists 

 to prejudge unfairly the allocation of organisms feeding by means of suc- 

 torial pseudopodia, in the face of the preponderating evidence in favour 

 of their animality which the totality of their history offers. It would 

 fail also, in the cases of the spermatozoa, which may be called the male 

 'gouidia' of most animals, and the male zooids, the ' complemental males,' 

 of a few animals, such as the Cirripedia. 



Irritability, contractility, locomotion and the ' cyclosis,' or circulation 

 of absorbed and assimilated nutritive matters, are phaenomena universal 

 in the animal, and occasionally observable in the vegetable kingdom ; 

 whilst the secretion of chlorophyll, and of cellulose, and the power of 

 regenerating an entire compound organism from a moi'C or less frag- 

 mentary portion, are properties nearly though not quite universal in 

 vegetables, and only occasionally noticeable among animals. It may be 

 anticipated that in the few cases in which it may at present be difficult to 

 decide with perfect certainty as to the animal or vegetable character of 

 an organism, an increase in our knowledge, if not of its very simple 

 structure, yet of its development, and if not of either its development or 

 its structure, yet of the development and structure of forms which by 

 gradual transitions connect it with undoubted animal or undoubted vege- 

 table forms, is likely at some time to enable us to place it in one or other 

 of these two kingdoms of life. But it must be said that there are organ- 

 isms which at one period of their life exhibit an aggregate of phaenomena 

 such as to justify us in speaking of them as animals, whilst at another 

 they appear to be as distinctly vegetable. A monad may at one period 

 be possessed not only of a nucleus and contractile vacuole, but of a cilium, 



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