250 



The result so far attained are as folllows :■ — 



Poutids of surcose per gallon. 



The difference on canes planted in 1900 and 1904, in pounds of 

 sucrose per gallon, has increased from '597 to "876, an increase of 4b' 

 per cent. Similarly, the difference on canes reaped in 1901 and 1904 

 has increased from *020 to "199. 



In considering this question it is essential that two points should 

 be clearly distinguished. Briefly put, it is the difference between 

 the maintenance of a ' sport ' and a gradual improvement by selection. 

 My meaning will be made clear by another reference to the case of 

 budding out thorns from citrus plants. If a bud is taken from a 

 spineless branch and the resulting tree comes spineless, then we may 

 have simple perpetuated a sport. But can we rely upon all such buds 

 being spineless ? This would appear not to be the case, for Mr. 

 Webber says : ' Standard varieties are now largely thornless' ; and 

 again. ' it is quite certain that thorns can be bred out in this way in 

 every case, and usually to do so requires but three or four generations.' 

 It is evident that we have here a gradual process, that the variations 

 between spineless and spiny buds are not uniform but differ in degree, 

 and, lastly, that continued selection is necessary before the spine can 

 be eliminated. The same fact is brought out — but in the contrary 

 direction— in the instance cited by Mr. Cradwick, where a tree grown 

 from a bud 1^ inches long attached to it produced thorns ove) 8 

 inches long ; it is obvious that it would be possible here also to 

 produce two divergent series of oranges — one becoming less and less 

 spiny and the other tending to produce longer and longer thorns. — 

 West Indian Bulletin— Vol. VI. No. 2. 



(It would probably be difficult to find a "sport" or a product of "bud 

 variation " which has] stood the tests to which well known varieties of seedlings 

 have been subjected for generations without reverting to an original type. 

 The selection of healthy cuttings or buds is obviously a course which it is the 

 interest of the cultivator to pursue for the elimination of all tendency to 

 disease, but the proof of improvement or alteration in the first special quality 

 possessed by the parent is not apparently very strong. The change effectod in 

 the spines of the lime and orange would assuredly be more easily and perma- 

 nent!}' effected by propagation from selected varieties raised from seed having 

 no spines shown to be possible by the raising of a spineless Lime in Dominica. 

 The subject is highly interesting and should be freely discussed. — Editor.) 



