NO. 1876. ON THE CRUSTACEAN ORDER CVMACEA—CALMAN. 



633 



The third maxiUipeds have the basis slender and shorter than the 

 distal segments together. The first legs are about equal in length 

 to the whole cephalothoracic region; the basis is 

 about three-fifths of the length of the distal seg- 

 ments together; the very slender dactylus is about 

 equal to the carpus and two-thirds as long as the 

 propodus. 



The second legs are also long and slender, consid- 

 erably longer than the carapace; the basis is about 

 equal to the distal segments together; the carpus 

 has a row of unequal spines along the inner edge 

 and is about equal to the last two segments 

 together; the slender dactylus is nearly four times 

 as long as the propodus; there is a well-developed 

 exopod. 



The third and fourth pairs of legs are similar to 

 one another, only a little shortcir than the carapace, 

 and each having a minute exo]Jod of two segments; 

 the basis is longer by one-half than the distal seg- 

 ments together. 



The fifth legs are very small, less than one-fourth 

 of the length of the preceding pair; the basis is 

 shorter than the distal segments together. 



The peduncle of the uropods is longer by about 

 one-haK than the last somite, and has a row of unequal spines on the 

 inner edge. The endopod is about equal in length to the peduncle, 

 of three segments, the first about three times as long as* either the 

 second or the third, spinose on the inner edge. The 

 exopod is a little longer than the first two segments 

 of the endopod and has setse on both edges. 



Remarks. — The specific identity of this form with 

 that to which I gave the name Platyaspis orhicularis 

 is not beyond doubt. The type specimen from the 

 west of Ireland is, however, very incomplete, lack- 

 ing the abdomen and most of the thoracic somites. 

 Its carapace is only about haK as long as that of the 

 specimen described above and it shows no trace of 

 oostegites. It is therefore quite probable that the 

 differences in the outline of the carapace and the 

 absence of the paired ridges on its dorsal surface in 

 the larger specimens may be due to the difference 

 in age. 



The Irish specimen was referred to the genus Platyaspis chiefly on 

 account of the general shape of the carapace. The more complete 



Fig. 36.— Paraiamprops 

 orbicularis, imma- 

 ture female, second 



LEG. 



^n 



Fig. 37.— P ar alamprops 

 orbicularis, i m m a - 

 ture female, third 



LEG. 



