SCIENCE-GOSSIP. 



1 9 y 



COMPARISON OF CEKATOPHYLLUM AND MYRIOPHYLLVM. 



The temperatures are the means of the week preceding the observation. Column A applies to ponds and rivers, columns B 



and C to ponds only. (Fahr. scale). 



A 



Observation. 



Plant. 



Germination Ccvaiophyllum 



Myrioph. spkat. 



,, M, alternifl. . . 



Budding and spring growth . . Ceratophyllum 



,, ,, . . M. verticill. . . 



,, M. spkat. 



Flowering Ceratophyllum 



,, M. spkat. 



Maturation of Fruit . . . . Ceratophyllum 

 6, Fairfield West, Kingston-on-Thames. 



Date 

 (in Ponds) 



May 



March 



March 



April 



March 



March 



June 



May 



August 



Mean. 



62° 



48—49 

 48—49 



55 

 48—49 

 48—49 

 66—67 

 62—63 



75 



B C 



Max. in shallows Max. in depths of 

 less than 6in. deep. 12 to 18 inches. 



7 o u 



52—53 

 5 2 —53 



62 



52—53 



52—53 

 75-80 



70 

 85—90 





50- 

 5°- 



50- 



66 

 80 



VEGETABLE SPORTSMEN. 



By Herbert C. Fyfe. 



/~\NE of the most interesting chapters in the 

 ^-^ history of botany is that which deals with 

 the insectivorous plants. It is not till towards the 

 end of the eighteenth century that we find any very 

 definite reference to this group. In the year 1768 a 

 botanist, Ellis by name, sent Linnaeus a drawing of 

 " Dioncea muscipula," or "Venus' fly-trap" as it is 

 popularly called. With this drawing, which was 

 accurate in all details, Ellis sent a description which 

 was quite the reverse. Linnaeus, when he received 

 the drawings and description of the plant, was 

 naturally much interested, but he could not bring 

 himself to believe that Nature intended the plant to 

 receive any nourishment from the animals it seized, 

 and so he said that what happened was probably 

 that as soon as the insects had ceased to struggle, 

 the leaf opened and let them go. He only saw in 

 these actions an extreme case of the sensitiveness 

 of the leaves, and he thought the working of the 

 leaves on a par with that of the sensitive plant. 

 The catching of the insects, in his opinion, was 

 purely accidental, and of no importance to the 

 plant. 



Linnseus swallowed a good deal of what Ellis 

 told him — the action of the lobes, the locking of 

 the rows of spines together— but his soul revolted 

 at the idea of the plant squeezing the insect to 

 death, and the awful manner in which, according to 

 Ellis, the wretched insect was run through the 

 body by the three small spikes fixed near the middle 

 of each lobe, was utterly repellent to his nature. 



Ellis also imagined that the juice which the plant 

 secreted was a lure to entrap the insects, but in 

 this and in other matters he was corrected by 

 Curtis, a botanist who lived in North Carolina, the 

 Dionwa district. Curtis pointed out that the juice 

 was a true digestive fluid poured out by the lobes, 

 like our own gastric juice, and not a lure. Passing 



over several years, during which period hardly 

 any important addition to our knowledge of 

 insectivorous plants was made, we find that in 

 the year 1868 an American observer, one Canby, 

 experimented on Diornza by feeding the leaves 

 with various tit-bits. He found that cheese 

 agreed with the plant horribly, turning the leaves 

 black, and in most cases killing the plant outright. 

 He believed that the fluid in the plant was actually 

 secreted, and was not the result of the decomposition 

 of the substance that the leaf had seized, and that 

 the plant used this fluid to entrap the insect. 



Dioncea muscipula stands at the head of the 

 Droseracea, or sundew order, of which there are no 

 known species. All members of this order exhibit 

 in one form or another an adaptedness to one end, 

 namely the catching and digesting of insects. 



None of the insectivorous plants shows such 

 perfection of structure, and such an elaborate and 

 guillotine-like apparatus as Venus' fly-trap. The 

 flowers of the plant have little in them to attract 

 attention ; it is the leaves of the plant which cause 

 the observer of nature's wonders to spend hours of 

 study and examination over it. One of these 

 patient observers was Charles Darwin, who in 1S75 

 gathered his notes together in the shape of a book. 

 Anyone who wishes to understand Darwin's methods 

 and the manner in which he built up, step by step, 

 line upon line, his great theories of evolution and 

 natural selection, cannot do better than consult the 

 pages of " Insectivorous plants" (Murray, 1875). 

 The greater part of this book is taken up by Drosera 

 rotundi 'folia, called by common folk the sundew, 

 which may be found on the commons of Surrey 

 and Kent. Drosera is very interesting, and well 

 repays study, but it does not possess the marvellous 

 structures which render Diontsa such a fascinating 

 study. 



