Zoology and Botany, 333 



growth of seeds, Professor Henslow mentioned the results of ex- 

 periments which he had tried upon seeds of a species of Acacia, 

 sent by Sir John Herschel from the Cape of Good Hope, with di- 

 rections that they should be steeped in boiling water before they 

 were sown. Some of these were kept at the boiling temperature 

 for three, six, and fifteen minutes respectively, and had yet germi- 

 nated very readily in the open border ; whilst those which had not 

 been steeped did not vegetate. It was suggested that these facts 

 might lead to beneficial results, by shewing agriculturists that they, 

 may possibly be able to steep various seeds in water sufficiently, 

 heated to destroy certain fungi or insects known to be destructive, 

 to them, without injuring the vital principle in the seed itself. — MT; 

 Hope mentioned a practice common in some parts of Spain, of 

 baking corn to a certain extent, by exposing it to a temperature of 

 150° or upwards, for the purpose of destroying an insect by which 

 it was liable to be attacked. — Dr Richardson mentioned, that the 

 seeds sold in China for the European market were previously boiled, 

 for the purpose of destroying their vitality, as the jealousy of that 

 people made them anxious to prevent their exportation in a state, 

 fitted for germination. Upon sowing these seeds he had neverthe- 

 less observed some few of them were still capable of vegetating. 



Mr Curtis exhibited some specimens of the terminal shoots of a 

 Pinus, which had been attacked by the Hylurgus piniperdat and 

 made a few remarks on the habits of the insect. 



Dr Daubeny communicated to the Section the partial results 

 which he had obtained from a series of experiments he was carry- 

 ing on at Oxford, respecting the effects which arsenic produces oa 

 vegetation. He was led to undertake these experiments from 

 having received a communication from Mr Davies Gilbert, in which 

 he stated that there was a district in Cornwall where the soil con- 

 tained a large proportion of arsenic ; and that no plants could grow 

 in it except some of the Leguminosse. By analysis, this soil yield- 

 ed him about 50 per cent, of arsenic, in the form of a sulphuret ; 

 the rest being composed principally of sulphuret of iron and a little 

 silica. He had already ascertained that a little of the sulphuret 

 mixed in soils produced no injurious effect on Sinapis alba, barley, 

 or beans ; and that they flowered and seeded freely when grown in 

 it. Although the want of solubility in the sulphuret might be as- 

 signed as a reason for its inactivity ; yet it was certainly taken up 

 by water in small quantities, and imbibed by the roots of plants. 



VOL. XXI. NO. XLIT. OCTOBKH 1836. Z* 



