1894.] MICROSCOPICAL JOURNAL. 271 



long ribbon-like fronds upon the surface at low tide, 

 and always in the tangle of sea-weed which is rolled by 

 the tide and wind on the shores. 



Arachnoidiscus Ehr. often studs this frond thickl3^ 

 It may be felt by the hand as the frond passes through 

 the fingers as one almost involuntarily reaches for it as 

 he passes over the ground which it frequents and it may 

 be seen glittering on the frond which it often encrusts 

 when the sun has dried the tangle on the beach. 



Isthmia nervosa loves the same habitat, and it laces 

 the surface and fringes the edges of the frond with its 

 zigzag chains. 



This plant is also often gray with encrusted Coconeis 

 scutellum, and others of the same genus or is frosted 

 with Nitschia or Synedra. 



On other sea weeds I have found Triceratium arcticum 

 in patches, woven and interlaced, chain on chain. 



An inexhaustible and clean lind of Atthya decora re- 

 warded my curiosity in noticing that the surf along the 

 Pacific shore was fairly yellow with some floating sub- 

 stance. This I have seen twice for a week at a time in 

 midsummer. 



The bronzed film that shines upon the surface of the 

 mud flats is full of interest because it seems composed 

 of diatoms in mass, pleurosigma mostly with occasional 

 Surirella gemma, all far more beautiful when found than 

 they can be after being cleaned for mounting. The 

 writer would be glad to know how to separate and clean 

 them in any quantity proportionate to their number as 

 found. 



Notes of personal observation might be drawn out to 

 great length and if from dilligent and careful collectors 

 would be full of interest. I have in these here given 

 only spoken of some of my most lucky finds. I should 

 be glad if others would do the same. 



