MALACOSTRACA C 
word Crustacea. Like that, it was originally adopted to 
distinguish such creatures as crabs and crawfish and 
prawns from such others as oysters and clams; not be- 
cause of the absolute, but because of the comparative 
softness of their shells. Were reasons wanted for dis- 
placing the name, they would not be difficult to find. 
Many of the Malacostraca have shells harder instead of 
softer than those of some Mollusca. In some Malacostraca 
the integument has ceased to be of the nature of a shell, 
a parasitic habit having cancelled the need for such a 
defence. Moreover, the term suggests a false contrast 
with the neighbouring sub-class of the Entomostraca, in 
which as a rule the shells or skin-coverings are still softer. 
The name Thoracipoda, not open to any of these objec- 
tions, has been proposed by Dr. Henry Woodward. But 
against this it may be urged that, by many students of 
the Crustacea, the word thorax is not admitted as a proper 
technical term, and among others it is disputed whether 
the word, if admitted, should apply to three, to seven, to 
eight, or even to nine, of the crustacean segments. 
Retaining, therefore, the ancient, familiar, and suffi- 
ciently euphonious word Malacostraca, the subdivisions 
of this sub-class may next be considered. ‘T'wo orders 
have been formed, named respectively the Podophthalma, 
or stalk-eyed, and Edriophthalma, or sessile-eyed, crusta- 
ceans. In the former the eyes are mounted upon stalks 
or peduncles, which are almost invariably movable ; in the 
latter they are in continuity with the general surface of 
the head, or, if raised above it, the ocular prominences are 
unjointed and immovable. That some species in both 
orders are blind, gives a certain vantage-ground for the 
disturbers of accepted names to follow their bent. These 
may also allege that the terms just explained have not 
been at any time in undisputed possession. The Podoph- 
thalma have also been called Decapéda, ten-footed, while 
the Edriophthalma have been called Tetradecapéda, or 
fourteen-footed, Crustacea. The second of these names 
has found but little favour, and the first has the dis- 
advantage that it would apply to some Crustacea that are 
