SHRIMPS AND PRAWNS. 87 



there closely attaclied itself. This contains a parasite 

 crustacean. On raising the horny cap, beneath which 

 it shelters, the intruder may he discovered keeping fast 

 hold of the branchiae, or gills of the prawn, who appears 

 to suffer no inconvenience, or injury, from the presence of 

 his companion. This curious little creature is the ^op?/- 

 7'us crangorum of naturalists ; the foregoing illustration 

 represents the common Prawn {P. serratus), with the 

 parasite attached to it. The shrimp form is not ex- 

 clusively confined to the sea and tidal rivers. Fresh 

 water lakes, ponds, and streams in many parts of the 

 world have their shrimp tenants of one kind or 

 another, many of them highly noteworthy for the 

 beauty of their organization. The fairy shrimp (Chiro- 

 cephalus diaphanus) is a well-marked example. This 

 eleo-ant little creature is occasionallv met with in the 

 fresh water ponds and pools of this country, and can at 

 tunes be obtained in the neighbourhood of London. 

 Its first appearance strikes the examiner as being most 

 remarkable. The ordinary position assumed by most 

 aquatic creatures, is not to his taste or fancy, so he 

 swims on his back, rising to the surface or sinking 

 away into deep water, just as his will may direct, and 

 gliding here and there, like some tiny elfin boat 

 endowed with vitality. Its colours are most charming 

 and exquisite, clear and transparent^ of a delicate sea- 

 green hue ; it floats like a shadow through the water. 



