5ß 



HISTOKY OF CRUSTACEA. 



Chap. VIT. 



and its results cannot be regarded at once as uni- 

 versally applicable ; tbus tlie young Hermit Crabs 

 retain the general aspect and mode of locomotion of 

 Zoeae, whilst the rudiments of the thoracic and abdo- 

 minal feet are growing, and then, when these come into 



action, appear at once in a 

 perfectly new form, which 

 differs from that of the 

 adult animal chiefly by the 

 complete symmetry of the 

 body and by the presence of 

 four pairs of well-developed 

 natatory feet on the abdo- 

 men.^° 



The development of the 

 Palinuridse seems to be very 

 peculiar. Claus found in the 

 ova of the Spiny Lobster 

 {Falinurus), embryos with a 

 completely segmented body, 

 but wanting the appendages 

 of the tail, abdomen, and last 

 two segments of the middle- 

 body; they j)ossess a single 

 median and considerably 

 compound eye ; the anterior 

 antennae are simple, the posterior furnished with a small 



^^ Glaucothoe Peronii, M.-Edw., may be a young and still symmetrical 

 Pagurus of this kind. 



1^ Fig. 27. Zoea of a Pdlsemon residing upon Bhizostoma cruciatum^ 

 Less., magn. 45 diam. 



Fig. 27 



