288 THE ARCTURUS ADVENTURE 



lizard, we must (1) imagine every shark and bar- 

 racuda, moray and grouper as taking toll for him- 

 self, and furthermore that the action of the spines 

 and poison is, in their case, only an exceedingly 

 disagreeable and distasteful, not a fatal one; or 

 (2) we must believe that every assailant is pois- 

 oned and dies immediately, when the result would 

 be simply, how soon all the sharks and groupers 

 would be dead from eating surgeonfish; and (3) 

 we may imagine an instinctive knowledge of the 

 dangerous qualities of the yellow-tails on the part 

 of sharks and others, induced by the gradual elimi- 

 nation of xesuruphagus individuals. 



Once the tremendous interest of this problem 

 became apparent, I was always on the lookout for 

 some hint of a bout between these grazing cows 

 and their enemies, but never did I see a menace 

 or a defense. Their lives were lived calmly, with 

 dignity, and wholly superior to the terrors and fears 

 which marked the movements, the activities and the 

 habits of most of the fish around them. Their 

 cousins, the surgeonfish with long, sharp, wicked- 

 looking spines were never as abundant or fearless 

 as these, although one would say they had a much 

 more effective means of defense. 



Another problem, quite as difficult of elucida- 

 tion, has to do with the near relations of the sur- 

 geons, the Chaetodonts or butterfly-fish, and 

 Balistids or triggerfish. So intermixed are the 

 characters of these three groups, — characters ex- 

 ternal and internal, both of the body organs and 

 of the skeleton, that systematists group the sur- 



