394 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 3 



PLATE 48 

 Fig. 1. Lophosiphonia 'villum, habit of Dawson 737, x 33. 



Fig. 2. Lopliosiphonia villum, basal portion to show creeping fila- 

 ment and attachment organs, x 57. 



Fig. 3. Lophosiphonia 'villum, a tetrasporic branch with a rela- 

 tively short row of tetraspores, x 92. 



Fig. 4. Lophosiphonia <villuTn, growing point of a young, vigorous- 

 ly growing branch, x 400. 



Fig. 5. Lophosiphonia z'illum, growing point at tip of an old 

 branch with slowing growth, showing typical development 

 of hairs, x 400. 



Fig. 6. Lophosiphonia villum, detail of cellular arrangement in 

 median optical view, x 225. 



Fig. 7. Lophosiphonia mexicana, detail of base and rhizoidal hold- 

 fasts of the type, x 58. 



Fig. 8. Lophosiphonia mexicana, detail of growing point, x 400. 



Fig. 9. Lophosiphonia mexicana, superficial view of cell structure 

 to show paired appearance, x 175. 



Fig. 10. Lophosiphonia mexicana, apical portion of tetrasporic branch 

 from a specimen from Clarion Island, x 250. 



