56 



PROFESSOR OSKAR CARLGREN ON THE GENUS PORPONIA 



Fig. 2. 



Fig. 3. 



Figs. 2 and 3. — Schematic sections through the oesophagus region of Porponia antarctica (fig. 2) and 

 Halcurias rarlgrcni (fig. 3). The position of the tentacles (the dark rings) is drawn in. The rect- 

 angular, dark figures on the mesenteries indicate the longitudinal muscles. The shaded liDes denote 

 the directive plane. In Porponia the ridges of the oesophagus are not drawn in. 



