78 THE FRESH-WATER FISHES OF EUROPE. 



backs ; and, failing 1 to find her, another female is brought to the nest. The 

 male in the same way rubs his side against the female, and passes through 

 the nest over the eggs. This process may be continued day by day until, 

 according to Von Siebold, sixty or eighty eggs are deposited, before the male 

 closes the exit. The male now watches over his treasure for the period of 

 incubation, which may vary according to the temperature of the water from 

 ten or fifteen to twenty-five or thirty days. During this time he defends the 

 nest against all invaders, and especially against the curiosity of his wives. 

 He enters the nest from time to time, and by movements of the fins circulates 

 the water; and, as the young become hatched, goes in search of food, which is 

 first prepared in his own mouth for their wants. And only when the young 

 are sufficiently developed to eat and swim does the parent allow them to leave 

 their first home. Five or six days after hatching, according to Fatio and 

 other observers, the male opens the nest and spreads its materials, upon which 

 the young fishes assemble. They are then three to four millimetres long, and 

 have a natatory membrane which extends along and around the body. This 

 disappears in ten or twelve days, when the fins begin to develop. The fish is 

 now five or six millimetres long. The number of young varies with the nest; 

 some observers record twenty to thirty, while others mention sixty to one 

 hundred. 



If the male is captured, Houghton records that the nest is attacked 

 by a crowd of hungry, marauding Sticklebacks, of all ages and both sexes. 

 In the ovary Dr. Giinther has counted ninety eggs ; Blanchard counted one 

 hundred to one hundred and twenty ; but Fatio, and other writers, have found 

 a smaller number. The ripe eggs are about one and a quarter millimetre in 

 diameter, and of a yellow colour. The breeding season varies according to the 

 locality ; and a male may have three nests between the 1st of April and the 

 end of June. They begin to breed at the age of one year, and are reputed to 

 live for three or four years. Where powerful carnivorous fishes abound, such 

 as Perch, Pike, Trout, Salmon, their numbers may be kept down, but the 

 Stickleback fights for life to such purpose that it is not often molested ; 

 indeed, Blanchard suggests that they might adopt for motto the French 

 proverb, " Qui s'y frotte s'y pique/' 



The Pike has been known to eject them from the mouth when captured. 



In France it is known as Epinoche ; in Germany it is Stacheljisch ; in Italy, 

 Spinarello; in Poland, Ciernik; in Sweden, Hundstagg or Stor Spigg. 



The variability of a Stickleback, though not so marked as that of a 

 pigeon or a dog, is so considerable that the best ichthyologists differ as to 

 the forms which shall be regarded as species, and those which they class as 

 varieties. There is no doubt that if the characters of the varieties were 



