30 THE GENESIS OF SPECIES. [CHAP. 



ties of the giraffe are supposed to have been favoured and 

 preserved. 



The argument as to the different modes of preservation 

 has been very well put by Mr. Wallace, 1 in reply to the 

 objection that "colour, being dangerous, should not exist in 

 nature." This objection appears similar to the one here 

 urged ; as it is here said that a giraffe neck being needful, 

 there should be many animals with it, while the objector 

 noticed by Mr. Wallace says, " A dull colour being needful, 

 all animals should be so coloured." And Mr. Wallace 

 shows in reply how porcupines, tortoises and mussels, 

 very hard-coated bombardier beetles, stinging insects and 

 nauseous-tasted caterpillars, can afford to be brilliant by 

 the various means of active defence or passive protection 

 they possess, other than obscure coloration. He says, 

 " The attitudes of some insects may also protect them, as 

 the habit of turning up the tail by the harmless rove- 

 beetles (Staphylinidse) no doubt leads other animals, besides 

 children, to the belief that they can sting. The curious 

 attitude assumed by sphinx caterpillars is probably a 

 safeguard, as well as the blood-red tentacles which can 

 suddenly be thrown out from the neck by the caterpillars 

 of all the true swallow-tailed butterflies." 



But, because many different kinds of animals can elude 

 the observation or defy the attack of enemies in a great 

 variety of ways, it by no means follows that there are any 

 similar number and variety of ways for attaining vegetable 

 food in a country where all such food, other than the lofty 

 branches of trees, has been for a time destroyed. In such 

 a country we have a number of vegetable-feeding Ungu- 

 lates, all of which present minute variations as to the 



1 See "Natural Selection," pp. 6075, 



