160 R. L. Heinig — Blind root-suckers of the Sunderbans. [No. 3, 



freely, even at an early age ; bnt perhaps the most curious adaptation 

 of all, of means to ends, is to be found in the development of blind 

 root- suckers. 



The following species of forest trees in the Sunderbans produce 

 blind root-suckers, namely, Sundri, Fussur, Amur, Keora, Ora, and 

 Bden (Avicennia officinalis, Liim.). 



The root-suckers are woody processes, growing in an upward direc- 

 tion, aud developed at irregular distances along the whole course of the 

 roots of the above-mentioned species. They project from 1 to 3 feet 

 above the surface of the ground, and apparently cease to make further 

 growth upwards when the apex has reached the level of the highest 

 spring-tides. Tbey are called blind from the circumstance that they 

 are destitute of buds, and incapable of producing buds under any 

 conditions. The portion below ground is often furnished with rootlets, 

 but the part above ground is invariably naked. The tender tops of 

 the suckers are frequently gnawed by pig and deer, but this does not 

 destroy their vitality, and only results in the formation of apical 

 knobs and bifurcations. 



The mechanical effect of the root-suckers of all the species that 

 develop them (except Bden) is to enormously increase the holding power 

 or grip of the roots on the soil, and thus to cause a far greater resist- 

 ance to be offered to the uprooting of trees by storms, and generally 

 to maintain the stems of the trees in an upright position ; to prevent 

 the erosion of the snrface soil during high-tide inundations ; to check 

 the force of the egress of flood- water, and to induce deposits of alluvial 

 mud ; to detain seeds floated on to the islands at high tide, and thus 

 aid in the natural reproduction of all species ; to arrest fragments of 

 fertilising wood debris that would, in the absence of the root-suckers, 

 be swept into the rivers. 



The accompanying plate illustrates the general form and- relative 

 length of the root-suckers of different species. 



Sundri suckers are far more numerous than those of any other 

 species, and their flattened shape renders them fit to fully exercise all 

 the mechanical functions noted above. The suckers of Pussur and 

 Amur are met with in the low-lying localities affected by trees of these 

 species ; they are consequently, as a rule, much longer than those of 

 Sundri. The suckers of Keora and Ora, species that are found only 

 on river banks, are short on the high ground of the banks and long 

 on the river-side. This accords with the general observation that the 

 upward growth of a sucker continues until its apex has reached the 

 level of high-water mark. 



