AND THE STRUCTURE OF PLANTS. 83 



shall soon find our definition untenable ; for while the Linnaean class of worms 

 affords instances, in perhaps every one of its orders, of animals destitute of 

 locomotion, and evincing- no mark of consciousness or sensation, there are 

 various species of plants that are strictly locomotive, and that discover a much 

 nearer approach to a sensitive faculty. 



However striking, therefore, the distinctions between animal and vegetable 

 life, in their more perfect and elaborate forms, as we approach the contiguous 

 extremities of the two kingdoms we find these distinctions fading awav so 

 gradually, 



Shade, unperceived, so softening into shade, ^ 



and the mutual advances so close and intimate, that it becomes a task of no 

 common difficulty to draw a line of distinction between them, or to determine 

 to which of them an individual may belong. And it is probable, that that ex- 

 traordinary order of beings called zoophytes, or animated plants, as the term 

 imports, and which by Woodward and Beaumont were arranged as minerals,* 

 and by Ray and Lister as vegetables, have at last obtained an introduction 

 into the animal kingdom,! I GSS on account of any other property they possess, 

 than of their affording, on being burnt, an ammoniacal smell like that which 

 issues from burnt bones, or any other animal organs, and which is seldom or 

 never observed from burnt vegetable substances of a decided and unquestion- 

 able character. Ammonia, however, upon destructive distillation, is met with 

 in small quantities in particular parts of most if not of all vegetables, though 

 never perhaps in the whole plant. Thus it occurs slightly in the wood or 

 vegetable fibre ; in extract, gum-mucilage, camphor, resin, and balsam ; gum- 

 resin, gluten, arid caoutchouc : besides those substances that are common to 

 both animals and vegetables, as sugar, fixed oil, albumen, fibrine, and gelatine. 

 There are some plants, however, that even in their open exposure to a 

 burning heat give forth an ammoniacal smell closely approaching to that of 

 animal substance. The clavarias or club-tops, and many other funguses, do 

 this. But a distinction in the degree of odour may even here be observed, 

 if accurately attended to. Yet the clavarias were once regarded as zoophytes, 

 and are arranged by Millar in the same division as the corals and corallines.t 

 M. de Mirbel, in his very excellent treatise " On the Anatomy and Physio- 

 logy of Plants," has endeavoured to lay down a distinction between the ani- 

 mal and the vegetable world in the following terms, and it is a distinction 

 which seems to be approved by Sir Edward Smith ; " Plants alone have a 

 power of drawing nourishment from inorganic matter, mere earths, salts, or 

 airs ; substances incapable of nourishing animals, which only feed on what 

 is or has been organized matter, either of a vegetable or animal nature. So 

 that it should seem to be the office of vegetable life alone to transform dead 

 matter into organized living bodies."^ Whence another learned French phy- 

 siologist, M. Richerand, has observed that the aliments by which animals are 

 nourished are selected from vegetable or animal substances alone; the 

 elements of the mineral kingdom being too heterogeneous to the nature of 

 animals to be converted into their own substance without being first elabo- 

 rated by vegetable life ; whence plants, says M. Richerand, may be considered 

 as the laboratory in which nature prepares aliment for animals. || 



* Phil. Trans, xiii. 277. f Parkinson's Organic Remains, i. 23, ii. 157, 158. 



J Several species of this genus of fungi have very singular properties : thus the c. haematodes has so 

 near a resemblance to tanned leather, though somewhat thinner and softer, as to be named oak-leather 

 tlub-top, from its being chiefly found in the clefts and hollows of oak-trees. In Ireland, it is employed as 

 leather to dress wounds with ; and, in Virginia, to spread plasters upon. 



There are some cryptogamic plants, and especially among the mosses, that can be hardly made to burn 

 by n y means. Such is the fontinella antipyretica, so called on this very account ; and which is hence 

 hi common use among the Scandinavians, as a lining for their chimney sides, and the inside of their chim- 

 way of preservation. So that here we have an approach to mineral instead of to animal sub- 

 stances, and especially to the asbestos and other species of talcose enrths. There is one species of byssus, 

 another curious genus of mo ;ses, that t;ikes the specific name of asbestos from this very property. It is 

 found in the Swedish copper mines of Westmann-land in large quantities, and when exposed to a red heat, 

 instead of being consumed, is vitrified. 



ft Traite d'Anatomie et de Physiologic Vegetale, i. 19. 



y Elcmens de Physiologic, &c. cap de la Digestion 



F2 



