1280 NEW YORK STATE MUSEUM 



PLATE 21 



Hughmilleria socialis sp. nov. var. robusta var. nov. 



Page 1097 



1 Fragment of carapace showing relatively great width and 

 abrupt postabdominal contraction. Natural size 



2 First ring segment showing division of its posterior edge 

 into two lobes. Natural size 



3 Incomplete metastoma. Natural size 





