226 



THE YOUNG 



NATURALIST. 



maximum at its greatest intensity of 

 about 20° F. above the surrounding 

 air. Some observers have even noted 

 a difference of from 25 ° to 27 ^ But 

 even this is only a feeble heat com- 

 pared to that of another member of 

 the same natural order, a native of the 

 Mauritius, where the heat of a single 

 spadix was found to be 129^, whilst 

 the neighbouring air was only 79°, a 

 difference of 50°. A thermometer 

 placed in the centre of five spadices 

 showed an increase of 56°, and in the 

 centre of twelve spadices of 67° above 

 the adjacent air. This evolution of 

 heat, like all combustion, is accom- 

 panied with a consumption of oxygen 

 and a liberation of carbonic acid gas. 

 Whilst the starchy constituents of the 

 plant are converted into glucose or 

 grape sugar, it is the same process 

 which is seen in the germination of 

 seeds, and it is very evident in the 

 manufacture of malt from barley. A 

 similar phenomenon in a modified 

 degree takes place in all plants during 

 the formation and emission of the 

 pollen, but it is more marked and easily 

 observed in the Arum because the 

 flowers are closely clustered together, 

 and shielded from external influences 

 by the projecting and enveloping hood 

 of the spathe. The generic name of 

 Arum is of very doubtful etymology. 

 Some say it is the Greek " aronj^ 

 derived from the Hebrew "jaron " — a 

 dart, and of which the familiar name 



of "Aaron" is a form. I have heard 

 the boys in this locality call it "ear- 

 ring," doubtless a corruption of 

 "Aaron," although they say they 

 make earrings of the spadix. The 

 common names of the Arum are legion, 

 many of them given in allusion to its 

 fancied aphrodisical powers. One name 

 "bloody man's finger," doubtless refers 

 to the luried hue of the spadix ; and 

 " Starchwort " is evidently from its 

 economic use. Like all acrid and 

 poisonous plants, the Arum had at one 

 time a high medicinal reputation, 

 especially in rheumatism and gout, 

 but it has now fallen into disuse if not 

 disrepute. 



TO CORRESPONDENTS. 



All communications to be sent to J. E. Bobsok, 16, 

 Northgate, Hartlepool; or to S. L. Mosley Beau- 

 mont Park, Huddersfield. 



Subscriptions for Vol. III. are now due. 

 Weekly numbers or monthly parts, 6s.; 

 with plain plates ; or 8s. with coloured 

 plates. The latter cannot be obtained 

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 to the Editors. 



W.H. — Thanks, but we do not care to pub- 

 lish such paragraphs. That you send 

 looks very like a hoax. We should have 

 been glad to print that recording the 

 occurrence of the Bittern had you sent it. 



J.J.D. — Your Helix is nemoralis var. hortensis, 

 and small enough to be called hortensis 

 var. minor. 



Wanted, the present address of Charles 

 Roland, Esq., late Hemel Hempstead. 



