118 NATURAL HISTORY OF OUR SHORES 



is unrippled, often give a tremulous appearance to the 

 water, as if it were being peppered. 



The Malacostraca. This section is so very extensive, and 

 comprises so many diverse forms, that, although I have said 

 I would follow no systematic arrangement, it will be 

 necessary to attend to at least the " sub-orders," and I shall 

 take them as given in Glaus (" Text-book of Zoology "). I 

 know the system is open to some objection and so, in de- 

 gree, are all others but doctrinal points need not delay us, 

 and an enumeration of the characters that divide the " sub- 

 orders," " families," etc., would do so to great extent. 



It will be sufficient to say that the Malacostraca are 

 divided into two great sub-divisions, generally spoken of 

 as the " Sessile-eyed Crustaceans " (Edriophthalmata) and 

 the " Stalk-eyed Crustaceans " (Podophthalmata), characters 

 obvious to the wayfaring man the first division having 

 immovable eyes, little, or not, raised above the surrounding 

 shell, and the latter having the eyes on stalks, as in the 

 lobster, prawn, etc. 



The first sub- order of the " Sessile- eyed " is the Amphi- 

 poda. These have different forms of legs viz. some for 

 walking, and others for swimming, and for jumping. The 

 eggs are developed in a brood sac, placed under some large 

 projecting plates^ formed by the first body segments. 



The young of some species when first hatched follow 

 the parent in a little shoal, returning to the shelter of the 

 shield plates, like chicks beneath the mother's wings, when 

 danger threatens. 



A common example of the Amphipods is the " sand- 

 hopper " (Talitrus locusta), which abounds on all sandy 

 shores. 



This species can hardly be said to be " marine " " mari- 

 time " would be better for it lives buried (by day) in the 

 sand just above high- water level, where only the dampness 

 can reach it. 



