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PEOCEEDINGS OF THE NATIOISrAL MUSEUM 



VOL. 79 



differ from Marria in having five pairs of biramous feet, the first of 

 which is attached to the cephalothorax and the others to the thoracic 

 somites. On the other hand, the strong development of plumed 

 hairs in the pelagic forms may well be duplicated in Marria. Some 

 of the members of the family Peltiidae of the suborder Podoplea 

 have even flattened bodies, somewhat like isopods and probably 

 Mo.rria. 



Finally, the close resemblance of our form to the nauplius of 

 many crustaceans, among them even the Cirripedia and Malaco- 



ri'iGUREi 2. — Nauplius larva of Lepas fascicularis, X 10. A^, A^, First and 

 second anteunae ; B, brain ; E, eye ; H, frontolateral born ; M, mandible ; 

 S, stomach. (After Groom) 



straca, is undoubtedly most striking. These bear not only a single 

 eye but also two pairs of large biramous swimming legs, formed by 

 the second pair of antennae and the mandibles. These biramous 

 limbs, as, for example, in the nauplius of Lepas (see fig. 2), bear a 

 large number of long spines, which in turn are set with stiff setae, 

 the whole producing an organ strangely resembling that of Marna 

 in which the spines are further developed into jointed secondary 

 branches (endites and exites). As we can not be certain that the 

 two pairs of swimming limbs of Mama represent the first and 



