280 K. STEPHENSEN. 
in my specimen. The telson is much narrower at the base than shown 
by Sars. 
St. 118, specimen Nr. 2 (Figs. 20—21), 9, length 16mm. With 
regard to this specimen, the same may be said as of the foregoing; it 
Fig. 20. Pseudalibrotus Nanseni Nr. 2 (9). 
resembles Pseudalibrotus Nanseni in p7 but differs somewhat in other 
features. The small marsupial plates (shown on p4) mark the specimen 
as a 2; it is not mature, however, as the marsupial plates lack the usual 
bristles along the edge. 
The lateral lobes of the cephalon are slightly shorter and less poin- 
