424 



swingle: a salt-tolerant citrous plant 



in mangrove swamps and tidal forests would naturally lead us 

 to expect that it possesses high powers of ''alkali resistance," 

 since sea water contains over 3 per cent of dissolved salts and the 

 mangrove and other plants growing in the niangrove swamps 

 are able to withstand large quantities of dissolved salts in the 



• Fig. 2. Merope angulata. A, flower; B, pistil; C, stamens; D, seed; E, fruit; 

 F, longitudinal section of fruit; G, cross section of fruit. A-C, scale 1.5 ; D-G 

 natural size. 



substratum. Experiments carried, on with seedling plants in 

 the greenhouses of the Department of Agriculture at Washing- 

 ton have shown that it is indeed very resistant to salt. One 

 plant which was watered exclusively with a normal salt solution 

 showed no ill effects for two months. The treatment was con- 

 tinued and the plant finally died, the soil containing at the time 

 of its death 1.34 per cent salt (computed from readings by 

 electrolytic bridge). Another plant was given 1.5 oz. normal 



