ANIMALS FOR. 43 



Nor is this habit confined to the fresh- water stickle- 

 backs. A lady, writing to me from Aberdeen, and 

 describing her Aquavivarium, says : " A fifteen- 

 spined stickleback (Gasterosteus spinachia) con- 

 structed a nest on a piece of rock, which was covered 

 with a fine green seaweed, depositing the spawn 

 first, then covering it with loose seaweed, and lacing 

 all together with a long thread, composed, apparently, 

 of some secretion. The fish afterwards, for about 

 the space of three weeks, watched the nest, never 

 leaving it at all, save for the purpose of driving 

 away the other fish when they approached too 

 near. When a stick was introduced into the 

 vicinity of the nest, the fish would fly, open- 

 mouthed, to attack ib, and would bite it with great 

 apparent fury. At the expiration of the above- 

 named time, the young fry made their appearance 

 by hundreds ; but I am sorry to say they soon dis- 

 appeared, being devoured by the other fish, and 

 caught by the tentacles of the sea-anemones. The 

 mother fish continued her attendance at the nest 

 as long as any of the young fry were left." 



The stickleback is very tenacious of life, and will 

 live out of water for several hours. I was walking 

 a few mornings since on the sea-shore where some 

 fishermen had left the refuse of their nets the night 

 before ; all the animals were dead except a solitary 

 stickleback, who still survived, and on being placed 

 in the sea, scuttled off again as though nothing had 

 happened. The fresh-water species are often taken 

 at sea at the mouths of rivers, and Sir Edward 

 Belcher informs me that he took a specimen whilst 

 dredging at sea during the last Polar voyage. 



There are seven British species of the genus 

 Gf aster osteus, all known by the name of Stickle- 

 back. This name has been given them from the 

 sharp spines which, in common with a large section 



