MINOR MASONS 7 



squirted up by the wheels of a passing cart, may be 

 seen. The one suspicious fact about it is that it is the 

 only mud- splash there. If opened with a knife, neat 

 cells made of pellets and shaped like jars will be found 

 holding the eggs or larvae of the bee. Sometimes one 

 or two neat little jars of masonry are found merely 

 stuck on to a wall. 



Mason birds have a great affection for an old nesting- 

 place. It seems as if the same feeling were shared by 

 mason insects. Some years ago a mason wasp made a 

 cell inside the keyhole of a bureau in a bedroom ; when 

 the bedroom door was shut, it used to come in through 

 the keyhole in the door. Next year this bureau keyhole 

 was again tenanted by a mason wasp ! One small British 

 fresh-water fish builds stone breakwaters to protect its 

 eggs from being washed away by the current, much in 

 the same way that the pedrero bird makes a sangar. 

 This is the lamprey, a very curious creature, formerly 

 very common in the Thames, whence they migrated 

 to the brackish waters of the estuary at certain seasons. 

 Charles St. John watched a pair of these little fish for 

 some time at work in a running ditch, painfully col- 

 lecting stones and pushing them up into little heaps. 

 The stones were apparently pushed ; but it is more 

 probable that they were carried in the sucker-like 

 mouth of the lamprey. 



