14 BLAKE: REVISION OF THE AVOCADOS 



Limon, May, 1903, Cook & Doyle 476. San Jose, April, 1903, Cook & 

 Doyle 2. 



Panama: Around Culebra, Jan., 191 1, Pittier 2144. 



Bahama Islands: Nassau, New Providence, 1903, Curttss 116. 



Cuba: Santiago de las Vegas, 1905, Abasco 4556. 



Santo Domingo: Without definite locality, 1871, Wright, Parry, 

 and Bnimmel. 



Porto Rico: Cabo-Rojo, 1885, Sintenis 759, 759^. Ponce, 1903, 

 Prey 69. Caguas, 1899, Heller 931. 



St. Thomas: 1881, Eggers. 



St. Croix: Big Princess, 1896, Ricksecker 305. 



Martinique: 1871, Hahn 350. Without date, Duss 1948. 



Grenada: Belmont, St. Georges, 1905, Broadivay. 



Colombia: Vicinity of Santa Marta, 1 898-1901, Herbert H. Smith 

 1760. 



Bolivia: Cochabamba, 1891, Bang 1162. 



Brazil: Botanic Garden, Para, 1908, Baker 59. 



Philippine Islands: Cultivated, Manila, Luzon, 1919, Merrill 

 6347- 



This is the first known of the avocados, and is by far the commonest 

 and most widely cultivated in the American tropics and in the tropics 

 of the Old World. It is undoubtedly a native of tropical America, 

 but specimens which were certainly indigenous where found are nearly 

 or quite unknown. 



Of the three races distinguished by Mr. Popenoe, whose key has al- 

 ready been cited, the first or "Mexican type" is here separated as P. 

 americana drymijolia. The other two races, called by Mr. Popenoe the 

 West Indian and the Guatemalan, respectively, do not appear to show 

 distinctive characters of botanical importance, however significant 

 their dift'erences in fruit and fruiting season may be from the horti- 

 cultural point of view. At any rate, I have failed to find any differences 

 whatever in the abundant herbarium material examined, and am con- 

 sequently compelled to treat the West Indian and Central American 

 forms as a single species. 



Specimens collected by Merrill in Manila, where the plant has re- 

 cently been introduced, show an interesting abnormality in the floral 

 structure, one or two of the staminodes being antheriferous in addition 

 to the normal fertile stamens. They are about 4 mm. long, with the 

 hairy filaments about 3 mm. long, bearing laterally near the middle one 

 or two sessile adnate glands; the anthers are 4-celled, with the two lower 

 cells laterally dehiscent, the upper cells introrse. This occasional con- 

 version of the staminodes into stamens was long ago noted by Meissner.^ 

 « DC. Prodr. 15I: 53. 1864. 



