66 INVERTEBEATE ANIMALS. 



eyes. The Squilla, or Mantis-shrimp, so called from 

 its resemblance to an Orthopterous insect, exhibits most 

 of the body segments with their appendages perhaps 

 better than any other Crustacean. The larger species 

 are tropical, and it is probable that the animal, like the 

 Mantis, waits the approach of its prey within the reach 

 of its truly formidable fore-legs. Estimated number of 

 species : recent, 50 (M. Edwards) ; British, 18. 



Order DECAPODA. Uku, ten ; iroug, a foot. Gills 

 contained in cavities at the sides of the carapace. Pairs 

 of feet, five, the first pair at least chelate, i. e. termi- 

 nated by nipping claws. Includes Shrimps, Prawns, 

 Lobsters, and Crabs. 



Many of the finest examples were obtained, from W. Haeper Pease, hy 

 whom they were collected in the Pacific. 



Tribe MACROURA. ^axpoc, long ; oupa., a tail. 

 That which is commonly called the tail is in reality 

 made up of segments of the abdomen, which in the 

 present tribe is terminated by a fan-shaped swimming 

 appendage or fin, obviously acting to the greatest advan- 

 tage when, by its powerful down-stroke, it propels the 

 animal backwards. 



Group 167.— Family PAL^MONID^. Prawns, PalcBinon, 

 differ from Shrimps in the position of the segments 

 bearing the antennse, and in the carapace, which in 

 the^Prawn is generally keeled and extended in the form 

 of a sharply-toothed beak, but in the Shrimp is depressed 

 and unarmed. Prawns whilst living are objects of great 

 beauty, and in warm climates often exhibit vivid colours 

 and attain a large size. Mr. Gosse notices the curious 

 fact that Prawns taken from the obscurity of deep holes 



