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the water is quiet and free from wave action, there is a very 

 obvious zonation. The zone next to the open water is charac- 

 terized by Jiissiaea repens and Ipomoea aquatica, both of them 

 forming dense floating mats, and usually growing together. 

 The width of these mats is apparently determined chiefly by 

 the current, rather than by the depth, although we had no op- 

 portunity to observe the relation of the seedlings to the depth 

 of water. Jussiaea is noteworthy for its development of aeren- 

 chyma on special pneumatophores along the stem at each node. 

 These are adventitious roots, the nature of which is determined 

 wholly or in part by the position of the leaf from whose base 

 they arise. If the leaf is at the side or under surface of the stem, 

 the roots are usually normal and positively geotropic; if on the 

 upper side of the prostrate stem, all or most of them become 

 pneumatophores and are negatively geotropic. Their size at 

 maturity averages about an inch long by a quarter of an inch 

 through, and there are three to seven at each node. 



Behind the floating mat comes a reed thicket, in which Phrag- 

 mites karka is most conspicuous and may be ten feet tall. As 

 the soil accumulates and becomes firmer and drier, shrubs of 

 Pithecolobium dulce and thickets of bamboo appear. These 

 are in turn followed on still drier ground by coconut, banana, 

 and other cultivated species, and the river banks are populous 

 with fishing villages. 



Pagsanjan is the cleanest, most picturesque, and most attrac- 

 tive village that we saw in the Philippines. Its streets are 

 shaded with immense coconut palms, and the surrounding country 

 for some miles around is covered with coconut orchards. In 

 the city, almost every stage in the preparation of coconuts may 

 be observed, but it is all carried on by native methods without 

 the use of modern machinery. 



The coconut orchards are usually planted in regular rows, 

 and the trees may be eighty feet tall. Most of them show some 

 crook or defect in the stem, the result of some typhoon in the 

 past, and a few of them are actually prostrate at the base. The 

 terminal portion which grew since the typhoon is, of course, 

 erect. None of the orchards is carefully tended or kept free 



