208 THE DOCTRINE OF DESCENT. 
discovery of Fritz Miiller’s that a shrimp (Peneus) still 
begins its development as a Nauplius ; whereas all the 
other members of the order, as far as they are known, 
leave the egg in the higher Zoea phase (p. 50). As of 
the hundreds of .stalk-eyed crabs, scarcely a dozen have 
been hitherto examined as to their development, it 
will not be doubted that, with regard to the Nauplius 
phase, some resemble the Peneus of the Brazilian coast. 
But even were this case to prove unique in the order, 
it would suffice as a living witness of the connection 
Fic. 17. Axolotl. 
between the presence of the decapods and the primor- 
dial crabs. There can be no other view of this subject. 
The Nauplius phase in the development of the Peneus 
is either a shining testimony in favour of the doctrine 
of Descent, or a senseless paradox. 
