HYGROSCOPICITY 



165 



III. Variable Seeds. (Hygroscopicity variable.) 



(Variable seeds are those where some are permeable and others impermeable, the pro- 

 portions being very inconstant, so that the hygroscopic range for different seed-samples 

 would vary much, and could only be characterised as intermediate between that for im- 

 permeable seeds (nil) and that for permeable seeds (2 to 4 per cent.). 



Abrus precatorius 



Acacia Farnesiana 



Albizzia Lebbek ...... 



Aquilegia (species of) . 



Bauhinia (species of) 



Csesalpinia Sappan (A), mostly permeable . 

 ,, (B), mostly impermeable 



Csesalpinia sepiaria . . . . . 



Canavalia obtusifolia ..... 

 Canna indica ...... 



Cassia fistula 



,, marginata ...... 



Entada polystachya (A), mostly permeable . 



,, (B) ,, impermeable 



Enterolobium cyclocarpum .... 



Erythrina corallodendron .... 



,, indica ...... 



Ipomoea tuberosa ...... 



Poinciana regia ...... 



Tamarindus indicus 



Thespesia populnea ..... 



Hygroscopic 

 range 



(variable in 

 different 

 samples). 



o'5 per cent. 



I'S .. 



2'0 ,, 



07 „ 



o-S .. 



3"o ., 



o'6 ,, 



2'0 ,, 



o'3 .. 



0-3 „ 



0-6 ,, 



07 ,, 



2"0 ,, 



0'2 ,, 



o'6 



o'S .. 



I "o ,, 



conclusions 

 drawn from 



From the results of the observations on the hygroscopicity of 



a number of seeds which are given above it may be inferred — 



(i) That permeable seeds under ordinary weather conditions General 



vary to the extent of 2 or 3 per cent, of their weight 



in the course of two weeks, though the range may the author's 

 . ' o ,. . observations 



be reduced to i per cent, m equable conditions, and 



increased to 4 or 5 per cent, when the weather is 



characterised by extreme changes ; 



(2) That impermeable seeds have practically no hygroscopic 



reaction, such small changes as do occur, as of i in 



1000 or of I in 10,000 of the weight, being either 



instrumental or connected with loose tissue adhering 



to the scar or to the raphe ; 



