240 



The Plant World 



almost devoid of stick or leaf and many bushes and trees are 

 to every appearance dead. When the rains come on in July or 

 August, Tribulus terrestris and Kalstroemia maxima cover the 

 roadsides and plains, numerous weeds form a rank growth in 

 the coaconut groves and cane fields, and on the hillsides various 

 shrubs, among them Capparis, Cassia, and Bauhinia, are in leaf 

 and flower 



A highly interesting comparison is made at some length be- 

 tween the flora of Margarita and that of other regions, which, 

 however, can not be reproduced here. It may be said in brief 

 that from such comparison it is evident that the flora of Margarita 

 is largely composed of plants common to many parts of the Amer- 

 ican tropics, but that it contains twice as many plants character- 

 istic of South America as are characteristic of the West Indies, 

 and finally that while Margarita has some plants common to all 

 the islands about the Caribbean Sea, yet as a whole it has a flora 

 quite distinct from the northern islands and at the same time 

 closely approaching that of the Venezuelan islands and the north 

 coast of the mainland. 



The Reproductive Characteristics oj the Lodge pole Pine by 

 Gordon E. Tower, in the Proceedings of the Society of 

 American Foresters (Vol. IV, No. 1), brings out the interesting 

 fact that there is a well-defined and very distinct variation in 

 this species associated with a particular quality in one of the 

 physical factors of its environment The presence or absence 

 of lime in the soil not only affects the general appearance of 

 the forest but has an important bearing upon the opening of 

 cones and the production of seed. Trees growing on a sandy soil 

 poor in lime produce cones which open at maturity, or very soon 

 after ripening, and do not persist long on the trees. On the 

 lime soil the cones are very persistent, rarely opening on the trees 

 at maturity, and often remaining closed for thirty or more years- 

 Furthermore, the time and very often the manner of seed dis- 

 semination becomes greatly altered in the two forms. In the 

 lime-form, too, the cones are closed very effectively, the 

 scales being pressed tightly upon one another, making an her- 

 metically sealed chamber, impervious to water, in which the 

 vitality of the seeds is preserved for a very long time. 



