310 Pub. Pugct Sound Biol. Sta. Vol. 2, No. 52 



PLATE 53 



DIAGRAMS 



Fig. 1. A 4-ribbed specimen with no variation in the number of ribs 

 thruout. 



Fig. 2. An injured frond which shows almost complete disappearance 

 of the injured rib. 



Fig. 3. Showing variations of the midrib. 



Fig. 4. Showing variations of the midrib. 



Fig. 5. A 6-ribbed type, showing variations of the midrib. 



Fig. 6. A 6-ribbed type. 



Fig. 7. A 6-ribbed type. 



Fig. 8. A 6-ribbed type, showing variations in the side ribs . 



Fig. 9. Most complex system of ribs found. 



