Habits and Adaptations 265 



environment is unceasing. Every last corner in which it can 

 by the most far-fetched means gain a foothold must be 

 utilized. This narrow strip of sand, at the very limit of the 

 tidal zone, is available only at fortnightly intervals, and yet 

 the grunion has arranged its whole life-cycle in such a way 

 as to take advantage of it. 



Every two weeks during the spawning season, which lasts 

 from March until July, the grunion mature. Every two 

 weeks their eggs become ripe, and it is with unfailing regu- 

 larity at the time of a spring tide that their sex products 

 press for release. At night, in great numbers, the fish con- 

 gregate in the surf. There they wait, rising and falling in 

 the long Pacific roll, until just after high tide. At the proper 

 moment something gives them the signal, and they begin to 

 come in. Like skillful surf-boarders, they ride the crests of 

 the waves, and they bounce and tumble along with the foam 

 until they land high up on the beach. There each female's 

 tail drills a hole in the dripping sandj into it she pours her 

 eggs, which are fertilized by the nearest malej and the fish, 

 except for the unfortunate few who fail to extricate them- 

 selves and are found dead the next morning up to their arm- 

 pits, so to speak, in sand, squirm their way back into the next 

 wave and are sucked out to sea. The mating act, including 

 the selection of partners, the digging of the nest, and the 

 deposition of the sex products, takes no more than sixty 

 seconds, and the whole spawning migration sets what must 

 be an all-time record for speed, for from the moment an 

 individual starts in on the crest of a wave until it is back 

 again in deep water cannot be over three minutes. 



The parents, having done what is called their duty, but 

 what in this case must be nothing but a pleasant and exciting 

 excursion, go on their way. The spring tide recedes, next 

 day's sun shines down upon the beach, and there, safely 

 buried three or four inches deep in the warm, moist sand. 



