J. B. S. Haldane 115 



from the original Primula sinensis which came from China 

 about a hundred years ago. Some of these are very- 

 beautiful, others are freaks. One, for instance, has a 

 great bunch of leaves around each head of blossom ; in 

 another the flowers are represented by small green knobs. 

 These crosses are being studied from the point of view of 

 pure Science. There is a laboratory in the garden, and 

 here new varieties are dissected, their colouring matter 

 analysed, and much information obtained which will 

 serve both Science and the scientific grower. 



In another house there were plum-trees in full bloom. 

 The windows of this house were carefully screened with fine 

 wire gauze so as to prevent any insect entering, for this 

 might cause the pollination of one bloom from another. 

 These blossoms were being artificially crossed, and each 

 branch bore a separate label showing the exact nature of 

 the crossing. 



Odd discoveries are made now and then. One concerns 

 the crocus and an aphis. If there is one form of insect 

 more pestilent than another in the eyes of the gardener it 

 is the aphis or green fly. It ruins roses, destroys broad 

 beans, and it will settle like a plague on everything in the 

 greenhouse. Ask the average gardener if he can imagine 

 any use for the green fly and his language will be pungent 

 enough to shrivel the leaves ; yet one of these aphids has 

 been proved to have a real use, for through it certain 

 crocuses assume that beautiful marbling which is so 

 greatly admired and so difficult to obtain. Now that the 

 secret is out marbled crocuses are likely to become much 

 more plentiful and cheaper than they have been in the 

 past. 



Like all or most scientists, Mr Haldane is a very modest 

 man. 



" I am," he said, " a rotten observer. If I have any 

 merit it is that of being able to devise experiments which 

 will clear up problems.' ' He has a great admiration for 



