Fe Ae POTTS 
PEATE 2 
Peltogasterella socialis, Kriiger. 
Figs. 5, 6, and 7. Stages in growth of the external sacs of Peltogasterella socialis, on Pagurus alaskensis. x 2. 
Friday Harbour, San Juan Archipelago, State of Washington, U. S. A. 
