THE CRUSTACEANS 



97 



Fig. 66; SAND FLEAS. 



Above: (Talorchesiia lon- 



gicornis). 



Below: (Orchesiia agilis). 

 Long Island Sound. 



which they feed. They are agile animals, leaping with remark- 

 able rapidity. In swimming they often progress on their sides 

 or upon their backs with feet vipward. 

 They are creatures chiefly of the shore 

 or of shallow water, although some closely 

 related species are found in the deep sea. 

 These minute animals are important scav- 

 engers, rapidly devouring all dead fishes 

 and other forms of decaying animal or 

 vegetable matter. They are themselves 

 devoured in immense numbers, often by 

 the identical species of fishes upon whose 

 dead bodies they themselves delight to 

 feast. 



OrcJiestia agills, Fig. GO, is the common 

 olive green or brown Beach Flea of our coast. 

 It grows to be not more than half an inch 

 long, and lives during the daytime under 

 masses of sea weeds which have been 

 thrown up upon the beach. It constructs burrows in the sand under 

 the debris, and when disturljed it leaps with remarkable strength 

 and agility. 



A still larger species is, (Talorchesiia longicornis Fig. 66J, 

 which is Avhite or gray in color, and about an inch long. It is also 

 a beach scavenger, and devours decayed sea weeds, feeding mainly 

 at niglit, and remaining hidden within its burrow during the day. It 

 appears never voluntarily to enter the water but is a good SAvimmer. 



The Wood Borer, or Gribble, (Limnorea lignoritmj, is related 

 to the sow-bugs and pill-bugs and belongs to the sub-order of Crus- 

 tacea known as Isopoda. The gribble extends from New York to 

 Nova Scotia, and is also abundant on the northern coasts of Euroi^e. 

 It is not more than one-fifth of an inch long, and has a flattened 

 body with fourteen segments, and seven pairs of short legs. The 

 Ijack is covered with short hairs to which foreign substances are apt 

 to adhere. It is dull gray in color and resembles a pill-bug, the simi- 

 larity being still further enhanced by its habit of rolling up into a 

 ball when disturbed. It can also leap and swim rapidly. This crea- 

 ture is most destructive to all submerged timber, devouring every 



