come true from seed, in so far as concerns the characteristics which 

 distinguish the group. 



This peculiar characteristic of coming true from seed, a thing 

 very rare among tree fruits, must be attributed in seedling mangos 

 to polyembryony, a phenomenon which has long been known to oc- 

 cur in mangos. While it has never been thoroughly studied, and 

 much remains to be learned about it, the investigations of Belling 

 have thrown considerable light on the subject. Belling, working 

 at the Florida Experiment Station in 1908, found that in one race 

 of mangos, known as No. 11 in Florida and Jamaica, mango in 

 Cuba, the seeds were commonly polyembryonic. ?". e. contained more 

 than one embryo, and gave rise to as many as eight or ten plants. 

 A microscopic examination of numerous young fruits showed that 

 these several embryos were not the product of fertilization of the 

 egg cell in the ovary (the normal method of producing new in- 

 dividuals in all the higher plants), l)ut that they arose as minute 

 vegetative buds in the nucellar tissue surrounding the egg cell. The 

 trees which they produce are, therefore, comparable to budded or 

 grafted trees, in that they should reproduce more or less exactly the 

 characteristics of the parent. Belling did not find a single embryo 

 which had developed from a fertilized egg cell, but it is possible 

 that the occasional trees of these well known seedling types which 

 do not come true may have developed from fertilized egg cells, and 

 would, therefore, be as capable of variation as ordinary seedlings 

 of other tree fruits. It remains to be shown whether the egg cell 

 ever develops into an embryo in polyembryonic mangos, and to what 

 extent they may be affected by cross pollination. No investigations 

 have been made with monoeml)ryonic mangos, such as Mulgoba, 

 Bennett and other grafted varieties grown in Florida and Cuba, 

 but with these we are not concerned here. 



As Cuba was known to possess a large number of interesting races 

 and types, it was thought worth while to demote the month of July, 

 1915 the season during which most of tiic mangos ripen to a 

 thorough investigation of Cuban mangos, in order to learn as much 

 as possible concerning their relationships, productiveness and other 

 characteristics, and to bring to light choice types which might be 

 worthy of propagation. This work was greatly facilitated by the 

 hearty co-operation of the Cuban Sub-Secretary of Agriculture, Sr. 

 Arias, who appointed Sr. Gonzalo ]\1 Fortun, Ayudante Tecnico of 

 the Departamento de Botanica at the Estacion Agronouiica Experi- 

 mental to travel with me through the island and assist in the inves- 

 tigations. I am also greatly inciebted to Prof. J. T. Crawley, 

 Director of the Estacion Agronomica Experimental, and to Prof 

 H. A. Van Hermann, Chief of the Division of Agricultural Vul- 

 garisation of the Department of Agriculture, for valuable assistance 

 in the work. 



Distribution of the Mango in Cuba. 



The mango is widely distributed throughout Cuba, but it was seen 

 most abundantly in the region around Habana, where it is a con- 

 spicuous feature of the landscape, and in the hills back of Santiago 



5 



