THE TERMITES 



so in Africa termite country may have a characteristic 

 flora. This will indirectly affect all the other animals, and 

 will also determine what crops can be most successfully 

 grown. 



The natives are well aware that the soil formed from broken 

 termites' nests is unusually fertile. To some extent these 

 insects do the work which in temperate countries is done 

 by earthworms. Worms drag dead leaves underground 

 and eat them, and incorporate dead vegetable matter into 

 the humus in a form which is suitable for plant growth. 

 Termites do much the same thing, and may be very im- 

 portant in dry climates in which ordinary decay would be 

 rather slow. 



CASTES 



So far the different individuals of which the colony is 

 made up have been only incidentally mentioned. The subject 

 is much more complicated than in other social insects, but 

 the nature of the castes and the factors determining their 

 development lie at the root of their whole social organisation. 

 There is a larger number of castes than in other social insects 

 and also a bigger difference between the simpler and most 

 advanced types. 



The eggs are laid singly except in the primitive Australian 

 genus Mastotermes ; in the latter they are laid in groups of 

 sixteen to twenty-four, stuck together in two rows. The 

 appearance of this egg-group is rather like the similar groups 

 laid by cockroaches. The eggs develop slowly, and even 

 at quite high temperatures (20-25 ° Q may take three to 

 twelve weeks to hatch, according to species and circumstances. 

 In the less specialised termites the rate of egg-laying is not 

 very high, perhaps two hundred to three hundred a year, 

 but in the higher forms extraordinary figures have been 



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