NOTES ON SOUTHERN MEXICO 



303 



Cordoba, and here, as in all parts of this 

 country where there is insufficient pas- 

 ture, the tops of the stalks are cut off 

 for fodder as soon as the corn is full 

 grown. At the same time the stalks are 

 also broken down just below the lowest 

 ear, so that the ears hang with the tips 

 down, a process known as "doubling." 



This custom of "doubling" was after- 

 ward found to be universal throughout 

 southern Mexico, both in dry and wet 

 regions. In dry localities it is employed 

 to protect the grain from weevils. The 

 corn is left in the fields often for months 

 and, except in rare cases, is there im- 

 mune from the weevils. In the moist 

 regions this practice allows the grain to 

 harden without injury from the rain, as 

 the ears shed water perfectly when hang- 

 ing. Doubling might be used to advan- 

 tage in parts of the United States when 

 there is excessive rain at the time of har- 

 vesting, such as the summer of 1906 in 

 the vicinity of Washington, where quan- 

 tities of corn were ruined through the 

 germination of the grains before the corn 

 was picked. 



Another important reason for this 

 practice in some parts of Mexico is to 

 protect the ears from parrots and parro- 

 quites. While the ears are erect the birds 

 can light on the side of the ear and open 

 the husks, but when the ear is pendant 

 they have no place to stand from which 

 the tip of the ear can be reached. 



Santa Lucrecia, which is situated at 

 the junction of the Vera Cruz and Pacific 

 Railroad with the Tehuantepec Railroad, 

 is the region of greatest activity for rub- 

 ber stock companies. About here and 

 for some distance south there is little or 

 no virgin forest, but the land is covered 

 with a luxuriant second growth. Numer- 

 ous rubber trees can be seen from the 

 railway, but they are all small. The 

 leaves, however, are fresh and green. 



From Santa Lucrecia south the rail- 

 road gradually ascends. Before reaching 

 the summit of the divide the country be- 

 comes broken and is covered with fine 

 large forests. North of Rincon Anto- 

 nio the land is open and rolling, cattle 

 abound, and the dry-land type of vege- 

 tation appears. 



From a botanical standpoint Rincon 

 Antonio would be a very interesting place 

 to spend one or two weeks. It is pleas- 

 antly situated and has what looks like a 

 clean hotel. The climate is dry and not 

 very hot. Trips could be made north 

 into the fine dense forests, which are as 

 wild and tropical as anything on the 

 Isthmus. To the south it is but a little 

 way to cactus forests, through exceed- 

 ingly rough and interesting country. This 

 region is sparsely inhabited and the set- 

 tlement is completely isolated. A study 

 of the agriculture of these people would 

 probably show plants with interesting 

 adaptations to drought and short season. 



We reached San Geronimo on the 

 evening of December 8. The inhabitants 

 are chiefly Indians, though there are a 

 number of Mexicans and Americans liv- 

 ing there who are connected with the 

 Pan-American Railroad, of which this 

 town is the western terminus. 



The country about is perfectly flat, 

 with hills visible in the distance in all 

 directions. The type of vegetation is 

 decidedly desertic, the strong winds 

 which blow for the greater part of the 

 time doubtless aiding in accentuating this 

 feature. 



The change from the continual climb- 

 ing and striving to reach the light that is 

 so apparent in the forests a few miles 

 north is very striking. Not that the 

 plants here shun the light, for the typical 

 shape is spreading — a form that secures 

 the greatest isolation — but it is as though 

 there was an effort on the part of each 

 species to get as close to the ground as 

 possible. The advantage gained by shad- 

 ing the roots and resisting the wind is 

 obvious. 



Another characteristic that is quite 

 general is the tendency to have finely 

 divided leaves, though the reason for this 

 is by no means so clear and would seem 

 to counteract the shading of the roots, 

 for the leaflets close during the middle 

 of the day, when the sun is brightest. The 

 possession of these characteristics causes 

 a number of only distantly related plants 

 to present an almost uniform appearance. 

 Thus what appeared to be a single species 

 forming a low tree with spreading top 



