Vol. Xni. No. 326. 



THE AGEICULTUEAL NEWS. 



Sl.T 



the.se plants, he jjoints out that some faihires were 

 owing, dinibtle.ss, to the tact that attention had not 

 been paid to the different kinds of soil required by the 

 two different species. 



The natural soil of the Sisal heini) ( Agave rigida, 

 var. sisalana) is that of a limestone formation: and 

 ]\Ir. Cousins says that it has been demonstrated that if 

 cultivated on such a soil this species will grow for 

 .se\eral years without poling. It must be remembered 

 that this premature poling is what the planter of Si.sal 

 hemp has to combat. He also says that cutting the 

 leaves at three ye;lrs, instead of four years has been 

 proved to render the plants less liable to premature 

 poling. 



As regards Heneipien (4//rtt'e rigida var., four- 

 croides), Mr. Cousins shows, by citing .several instances 

 of plantations visited by him in Jamaica, where it is 

 being grown experimentally, that this species can be 

 successftdly cultivated on dry alluvial .soils which are 

 Very deficient in limest()ne. 



Seeing that there is a gTowing demand fur the 

 fibre obtained from both these plants, it will probablj- 

 be to the ad\antage of the smaller West Indian islands, 

 if experiments, which are about to be made with these 

 plants, prove .succes.sful. There is a great deal of uiieidti- 

 vated land of limestone foiination in the drier islands, 

 which might profitably be put under .Sisal hemp: and 

 also in the same islands much land, deficient in lime- 

 strove, which at present bears only scrub that might 

 well be planted in Henequen. 



The Coco-nut and the Avocado Pear. 



In the Bidletin Agricole du Congo Beige foi- 

 March l!tI4, there are two very interesting and instruc- 

 tive articles, one on the cultivation of the coco-nut 

 palm, and another on the avocado peai-. 



Mons. P. Drowsil, the l)irecti>r of Agricultuie, made 

 notes on the cultivation of the coco-nut palm in various 

 tropical districts of Africa and Asia, which he embodies 

 in the article under consideration. For the best results, 

 he considers that the palms need a fairly light, well- 

 drained .soil. On such a soil they will flourish, from 

 sea-level up to about 700 feet, if the water-supply, 

 either fr<:)m rainfall or natural drainage is sufficient. 

 It is interesting to note that the writer confirms the 

 observations made by Mr. Jackson in Antigua, as to 

 the want of corresj)ondence between the size of the nut 

 picked from the tree and the weight of copra obtaina- 

 ble from it. This he seems to attribute to varietal 

 characteristics, and in this coimexion he mentions 

 several well-known types. Among the methods of 

 starting the growth of a coco-nut, that practised 

 in Java, of placing the nuts in a horizontal position 

 on a lattice of bamboo, shaded b}' coco-nut branches, 

 until the first leaf appears, is noteworthy. The ^vriter 

 makes many recommendations and suggestions as to 

 the cultivation of the trees fvnd the prepai-ation 

 of copra. 



The article on the avocado pear, by Mons. L. 

 Pynaert, is quite an exhaustive one. Points of interest 

 are; the description of a large number of varieties 



ti'om \arious parts oi the Tropics, among which is- 

 a seedless one; the attempts which are being made to 

 improve the fruit by seed selection; and the clear ■ 

 directions given for budding superior varieties on possibly 

 inferior seedlings. After some remarks on the diseases 

 of the avocado, the article concludes with some ad\ice 

 as to developing the market in temperate countries for 

 this tropical fniit. With cold storage, and proper selec- 

 tion, gi-ading and packing, he thinks there is a possible 

 future in store for the remunerative exportation of the 

 avocado from the Tropics. 



Modern Views on Heredity. 



The subject of heredity formed the subject to 

 Professor Bateson's inaugural address at the meeting of 

 the British Ass(jciation at Melbourne. The Gardeners' 

 Chronicle emphasizes the Professor's statement of the 

 difficult problem facing the modern student of heredity, 

 and the advances in knowledge made by means of the 

 Mendelian method of analysis. The starting point of 

 modern investigations is the conception that an Drganism 

 is foi-med by means of 'pieces of living material' derived 

 from the present organisms. Thus the characters of 

 the individual are determined by those of the germ cells 

 by the fusion of which the individual is produced. 

 But as the germ cells produced by an indi\idual are 

 not necessarily all alike, variations occur in the result- 

 ing organisms. 



The problem therefore may be stated thus: — If 

 a piipidation consists of members which are not alike, 

 but differentiated, how will their characteristics be 

 distributed auKjng their offspring? The object of the 

 Mendelian student is to discover this proportion of the 

 distribution of these characteristics, how variations 

 between two kinds of the same thing — fowls for 

 instance, or cotton plants, to use a West Indian 

 example — are distributed among their offsjjring. 



Sluch work has to be done along Mendelian and 

 similar lines before any more real light is thrown on 

 the gi'eat problem of the origin of .species. For although 

 the Darwinian hypothesis of the survival of the fittest 

 expi-esses a general truth applicable to the average 

 individual, it hardly explains the survival of the factors 

 of germ cells, on which factors the characteristics of 

 the individual depend. 



A great deal of what is called \ariation is only the 

 new combination of factors, and although there is 

 evidence that factoi's may be lost, and so their charac- 

 ters disappear, there is but little evidence at present 

 of the origination of new factors. 



Most of the new varieties of cultivated j)lants are 

 the result of deliberate crossing. Remembering their- 

 number, it becomes no easier to conceive of such 

 enormous deviations from tyjje coming to pass in the 

 wild state. As the evidence stands at present, all that 

 can be safely said in support of the doctrine of evolution 

 is that variation occurs as a definite event often pro- 

 ducing, however, a discontinuous result; and that the 

 succession of varieties comes to pass by the establish- 

 ment of groups of individuals owing their origin tO' 

 such isolated events. 



