.MOKl'HOLOGY OF THi; COPEi'ODA. 295 



its structure, to the Copcpoda, and observed that the degree 

 of segmentation presented in it corresponded with that of 

 Lernantltropus. But, as marking a further stage of retrogres- 

 sion, -we sec also the anterior pairs of feet transformed into 

 misshapen, unjointed saccuh, which participate in the produc- 

 tion of the reproductive materials. 



In this case, in the oral organs, the beak-like proboscis is 

 wanting, and, as in the Scqi/urhue, they are composed of 

 pointed, more or less curved, chitinous rods, whose number 

 we could not estimate at more than three pairs. Since the 

 two lowermost pairs, from their whole aspect, are jaw-feet, 

 and the first in form correspond with the mandibles, we find 

 that the palpi or laawillm are wanting. Closer examination, 

 however, shows the existence, between the mandibles and the 

 first pair of jaw-feet, of a rudimentary appendage, which, 

 although it was formerly noticed by me, and even described 

 as a palpus, I, nevertheless, did not then regard as the 

 equivalent of the second maxillary pair. But the explanation 

 of the palpi as the second pair of oral members may be 

 regarded as the more certain, since they not only correspond 

 with them in position, but because the preceding cephalic 

 members are homologous with the two pairs of antennas. 



The Lernpeopodfc stand at a still lower stage of morpho- 

 logical completeness, as in them, as a rule, all division of the 

 body into somites is wanting. In rare cases (very clearly in 

 Lernceopoda Galei), it is true, the first thoracic somites may 

 be distinguished as separate rings, but in this family the 

 thoracic members in general are no longer developed; al- 

 though the rudiments of them are present in the early larval 

 condition, in the form of swimming-feet,"^ in the full-grown 

 Lerujeopod they are no longer to be found, even in the form 

 of unjointed processes. The limbs which do exist represent 

 the antenntc, maxillae, and jaw- feet, and consequently are all 

 cephalic memljcrs, although ivi a very retrograde condition. 

 The first antenme are simple and few -jointed appendages, and, 

 in opposition to the antenna; of the second pair, have inter- 

 changed the external insertion with the internal (fig. 7 a) . 

 Tlie latter, that is to say, are situated on the frontal region, 

 on both sides of the anterior antenna^, and constitute two- 

 jointed, clasping organs, supported on strong, chitinous frames 

 , (fig. 7 b), whicli have been described by Nordmann as 

 "Kiefer" (jaws), and by Van Beueden as " machoires.'' 

 Moreover, that these parts correspond with the second pair 



* Ivollar's 'AiiiJiil. il. Wieu. IVriiseuins,' .'uid Nor d maim' s 'Mikro- 

 giapliiscbe Beitriige/ 2 Heft. 



VOL. I. NEW SET?. X 



