298 



CRUSTACEA. 



the still unsegmented abdomen is developed in the form of a flat 

 caudal plate. The spines of the dorsal shield recall the Protozoaea 

 stage of Lucifer. There is a long, forwardly-directed rostrum, a 

 short, unpaired median spine projecting backwards from the posterior 

 edge of the dorsal shield, while, springing from the sides, are two 



Fig. 141. —Several consecutive Erichthoidina stages (after Claus). a', first antenna ; <<". 

 second antenna; ai-a.6, the six pleopoda; I-V, the five niaxillipedes ; 6, 7, S, the threa 

 posterior thoracic segments which, in these stages, have no limbs. 



long postero-lateral spines (Fig. 141 A). Besides the Nauplius eye, 

 the paired stalked eyes are found on either side of the rostrum below 

 the dorsal shield. The two pairs of antennae are still short and 

 uiiiramose. The mandible has no palp, and the two pairs of maxillae 

 are present in a very rudimentary condition as small lobes. The five 



