2 3 6 



SCIENCE-GOSSIP. 



same family as the bladderworts, and have their 

 leaves sticky with a fluid exuded from the numerous 

 hairs scattered over the surfaces The leaves roll 

 up their edges over captured insects, and gradually 

 digest them. 



In Utricularia, or bladderworts, several species of 

 which occur submerged in our pools and rivers, 

 water-fleas and other insects are suffocated in the 

 bladders into which they appear to go for security 

 from other enemies. These bladders have the pro- 

 perty of absorbing and dissolving animal matter. 



To a casual observer these carnivorous plants 

 would appear to thrive as well without as with 

 nitrogenous food ; but, to settle that point, Pro- 

 fessor Francis Darwin fed a number of Drosera on 



roast meat. E very- 

 four or five days 

 they received a new 

 ration, and at the 

 end of two months 

 they were found in- 

 comparably superior 

 to the others that 

 were shut up in such 

 a way as to exclude 

 insects. The stems 

 and branches of the 

 former were stronger 

 and more vigorous, 

 while the leaves were 

 greater in number 

 and of a brighter 

 green, the flowers 

 were more abundant 

 and of livelier col- 

 ours. The plants 

 were compared even 

 to the seeds. Ap- 

 pended are the results of Professor Darwin's 

 experiments : — 



Experiments on' Drosera. 



Unfed. Fed. 

 Total weight of plants, excluding 



flower-stems ioo 122 



Total number of flower-stems - - 100 165 



Sum of heights of flower-stems - 100 160 



Total weight of flower-stems - - 100 232 



Total number of capsules - - 100 194 



Average number of seeds per capsule 100 123 



Total weight of seeds - - - 100 242 



Total number of seeds - - - 100 3S0 



These results show the benefit derived by the 

 fed plants, especially in the formation of seeds. It 

 is to be inferred from these experiments that plants 

 and animals have more points in common than 

 many are disposed to concede. We see that 

 nature, though sparing of causes, is prodigious in 

 effects, and shows a great variety of phenomena 

 having a common and unique origin. We further 



Bladderwort. 



learn that in the economy of the plant and animal 

 many of their functions are analogous. 



To our accustomed conception of a plant it 

 appears incredible that the Algae, a low form of 

 plant life, should develop animated seeds, seeds 

 having the capacity of locomotion; but one need 

 only observe their nimble movements in water to 

 be convinced of its truth. In the apparent enjoy- 

 ment of their youth they swim and gambol about 

 in all directions ; but as they grow older these 

 gambols cease, and they settle down to the earnest! 

 realities of life. They terminate their youthful 

 career by fixing themselves to some support and 

 there giving birth to a new plant. Their motive 

 phenomena are due to numerous appendages 

 developed on the surface of the seed, and which 

 propel them through the water. 



The sponge, a low form of animal life, also 

 develops locomotive seeds. The locomotion of 

 these germs is due to delicate cilia attached to 

 the posterior part of the cell. This germ is an 

 independent atom of living matter, and moves 

 through the water as if propelled by a will pres- 

 cient of its future destiny. It at length fixes itself 

 to some stationary object, and develops into a 

 sponge. 



On the boundary line between the two kingdoms 

 nature appears to delight in confusing the inhabi- 

 tants. It accords locomotive powers to plants in 

 the spermatic stage, while the animal seeds simi- 

 larly endowed give birth to immobile animals. 

 These elementary beings have identical modes of 

 reproduction — both divide to multiply. 



With so many harmonies we infer that instinct 

 is equally distributed. If locomotion is possible 

 without a nervous system, it is involuntary and 

 therefore instinctive. The cause of the motion is 

 within the seeds, and their subjection to that cause 

 is absolute. The motions of the seeds of Algae and 

 sponges are instinctive, and they fix themselves 

 instinctively to develop new creatures. 



We would seek in vain for essential differences 

 between the two great divisions of animated 

 nature. There is none. We constantly meet 

 with analogies among their phenomena. Plants, 

 it is true, have no mind nor will ; their acts 

 are purely mechanical and necessary. Every 

 plant has a special instinct that determines its 

 individualism. The Valisneria, the Ranunculus, 

 the Drosera, and a hundred others, have their 

 special instincts, and nothing can disturb their 

 rigorous uniformity. Some are more ingenious, 

 some more cunning, and some are more deceptive 

 in their habits. 



Among animals instinct is more marked than 

 among plants, but it is the same instinct. The 

 complexity of animal instinctive phenomena is 

 due to individual and organic peculiarities. The 

 same steam controls a whole factory and executes 



