Sept. 1, 1865.] 



SCIENCE-GOSSIP. 



205 



is borue at the tips of the fronds ; and this species 

 is recommended as the best for microscopical 

 examination. Professor Harvey advises that fresh 

 specimens should be collected in winter or early 

 spring, and, being removed from the water, should 

 be left till partially dry. As the surface dries there 

 will exude from the pores of the receptacle drops of 

 a thick orange-coloured fluid, which, on being placed 

 under a microscope and moistened with salt water, 

 will be found to be composed of innumerable 

 cellules, from which will issue troops of these atoms, 

 that are no sooner liberated than they commence 

 those singular motions which the naturalist finds it 

 so difficult to reconcile with vegetable life. 



But the species best known and most highly 

 appreciated by juveniles, though not the most 



Pis'. 3. Knotted Wrack {Funis nodosus), 



common, is the Knotted Wrack, or "Crackers" 

 {Fucus nodosiis). The air-vessels are very large, and 

 on being thrown into the fire burst with a loud 

 report; herein lies the cause of the popularity 

 alluded to. No distinct midrib runs up the fronds, 

 which are narrow and thickened. The receptacles 

 which bear the fructification are not terminal, as in 

 the former species, but borne on stalks or pedicels 

 issuing from either side of the fronds. In the 

 present species the spores separate into four, and 

 in the Serrated "Wrack into eight parts or sporules, 

 A parasitic sea- weed often grows upon and nearly 

 covers the Knotted Wrack. 



There is also a much smaller kind of wrack {Fucus 

 canaliculatus), the fronds of which are only a few 



inches in length. The fructification is borne at the 

 tips of the fronds, and the spores separate into two 

 sporules. Two other species belonging to the 



Fig-. 4. Small Wrack {Fucus canaliculatus). a 



same genus are found on our shores, but are less 

 common. 



Apropos of the name of " wrack " — which is com- 

 monly given to these plants of the sea, — in the 

 Channel Islands it is vraic, and this is derived from 

 the French varec, signifying sea-weed. So that in 

 using the word "wrack" we are employing a cor- 

 ruption of the French word for "sea-weed." 



If this brief notice of some of the common objects 

 of the shore should lead any to examine for them- 

 selves what they have never observed with any 

 interest heretofore, and to gather instruction from 

 what they have almost despised, our design will be 

 consummated. " There is nothing in nature so 

 common, but we may always learn something from 

 it, if we will but take the trouble to learn." 



Cultivation of Butterwokts. — Finguicula 

 vulgaris, and, indeed, any of the other species, may 

 be easily treated in a state of cultivation, by atten- 

 tion to the following method, successfully adopted in 

 our North Wales Botanic Garden. Collect the plants 

 while in a state of hybernation, any time between 

 November and March ; at that period of the year 

 they resemble bulbs, and can be picked off the surface 

 of the bogs and moors m abundance. Pill a saucer 

 with finely broken pieces of peat, and as much water 

 as can be absorbed by tlie peat, and then place the 

 bulbs simply upon its surface, without burying them 

 in, or beneath it ; just steady them and keep them 

 supplied with moisture, and they will soon strike 

 their fibres downwards and spread their leaves upon 

 the surface, and make a beautiful appearance during 

 the season. — W. F. in Botanists' Chronicle. 



