790 On the Homologies of the Crustacean Limb. [October, 



Camparison wth limbs of Cladocera. — We should naturally first 

 compare the appendages of the Phyllopods with the members of 

 their own order, and especially the Cladocera; and here, whether 

 we consider the carapace-valves, the eyes single and compound, 

 the two pairs of antennae, or the telson, we find a very dose con- 

 nection in form between Limnetis and Daphnia or Moina. In the 

 accompanying sketch (Fig. 3) from Gruber and Weismann's ex- 

 cellent paper on the Daphnidoe 1 (which we have slightly modified, 



1 the Phyllopod limb. 



introducing dots in the branchial portion) may be seen how nearly 

 the first leg of the male of Moina rectirostris agrees with that of 

 the male Limnetis, as seen in the sixth endite forming a claw like 

 that of Limnetis, although the flabellum is not clearly differen- 

 tiated from the endopodal portion of the limb. But when we 

 look at the third pair of limbs of the female of the same Clado- 

 ceran (Fig. 4 ), we find an epipodal portion (flabellum, ex, and 

 gill) differentiated from the endopodal portion of the limbs. The 

 endopodal portion in the Cladocera is not differentiated, and forms 

 a number of well-marked lobes or endites (Lankester), as in the 

 Phyllopoda ; this differentiation into six endopodal lobes being 

 peculiar to the Phyllopoda. 



The Cladocerous limb is intermediate in form and complication 

 inte Daphniden. 1877. 



