THE PRANIZAL. 
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able. Sometimes they are of a grass-green colour, or blue or ash- 
grey; and they are often transparent and dirty white. A variety 
of the common British kind is of a reddish-brown colour. Not only 
are they interesting on account of this peculiarity,, but they have 
also afforded much discussion concerning their relation to the crea- 
ture represented in the central figure, which belongs to the genus 
Anceus. M. Hesse, a distinguished French naturalist, made a great 
sensation amongst carcinologists some years since by asserting 
species OF Praniza and Anceus . 
that his researches had led him to be certain that the A nceus was 
the mature form of Praniza , and that the female Anceus' s eggs 
were developed into creatures like those represented above. Whilst 
he was pursuing his investigations, Spence Bate was completing 
some very careful researches upon this very subject, and the English 
naturalist arrived at very different conclusions. He showed that 
the young Praniza was not quite like its adult form, but that the 
resemblance was great, and that the young of Praniza coeruleata 
was more like Anceus than the lately-hatched of the other Pranizce. 
The distinctions in the anatomy of the genus Praniza and Anceus 
