26 BULLETIN 743, U. S. DEPARTMENT OF AGRICULTURE. 



if picked before they are fully mature. The best varieties, on the 

 other hand, are characterized by a delicate richness which is highly 

 pleasing to the palate. When combined with a smooth, fine-grained 

 flesh of attractive appearance, the result is a variety of excellent 

 quality. Many such varieties are found in Guatemala, yet they do 

 not constitute more than a small percentage of the total number of 

 trees. The proportion of good fruits varies in different localities ; in 

 some it is difficult to find a single one of really good quality ; in others, 

 such as Antigua and San Cristobal, as many as 10 per cent of the 

 trees examined may be quite satisfactory in this respect. 



Seed. — The size of the seed and its condition in the seed cavity are 

 the two points which interest horticulturists. With regard to the 

 latter, it may be said that, with a single exception, all the avocados 

 of the Guatemalan race which were examined had seeds which fit 

 snugly in their cavities, with both seed coats adhering closely to the 

 cotyledons. The exception noted was a variety from Amatitlan in 

 which the seed was loose in the cavity, as it often is in the West In- 

 dian race. Possibly this was not a true Guatemalan variety. 



The size of the seed is commonly larger in proportion to the size 

 of the fruit than is considered desirable by North American avocado 

 growers. This defect, in fact, disqualifies more of the varieties than 

 any other. Round or oblate varieties are especially likely to have 

 large seeds, but in an occasional one the seed is medium sized or even 

 small. Not every round avocado has a large seed, but until an ex- 

 amination has been made a large seed may be expected. 



Pyriform and elongated fruits are not so likely as round fruits to 

 have objectionably large seeds, yet in many instances they do have 

 them. The proportion of such fruits with comparatively small seeds 

 is not large. 



The best means of judging the size of the seed is by comparing its 

 weight with that of the entire fruit. If it is not over 10 per cent of 

 the whole fruit, it may be considered that the seed is small; if it is 

 15 per cent, it is not objectionably large; but if it is 20 per cent or 

 more, it is undesirably so. 



The shape o^the seed conforms to that of the fruit; oblate vari- 

 eties have round or oblate seeds, round varieties the same ; pyriform 

 and oval varieties have ovoid or conical seeds. The great extremes 

 in seed form which are found in the Mexican race are not seen in the 

 Guatemalan, the range being from oblate to conical. The cotyledons 

 are always smooth or nearly so, differing in this respect from those 

 of the West Indian race, which are often rough and warty toward the 

 apex. 



CLIMATIC CONDITIONS IN THE PRINCIPAL AVOCADO REGIONS. 



Climatic conditions are by no means uniform throughout that por- 

 tion of the Guatemalan highlands in which avocados are grown. 



