Objects for the Microscope. 189 



in rock pools much exposed to the sun it hangs in dirty 

 yellow bunches, and for that reason is often unrecognised. 

 The rare Laurentia tenuissima is found plentifully in the 

 Channel Islands. 



The fructification of Laurentia is both various and 

 remarkable, requiring microscopic investigation. 



1. It has broadly ovate capsules, about the size of a 

 poppy-seed, containing red, pear-shaped seeds, supported 

 upon narrow stalks. A section must be made through the 

 capsule to show them well. 



2. Ternate granules imbedded in the ramuli, or tips of 

 the short branches. Simply magnified they appear to be 

 dotted. A transverse section should be made. 



Then, again, on some specimens of the same plant may 

 frequently be found swollen tips, forming large spurious 

 capsules, and these are very curious. Some of them have 

 only a minute pore ; others are spread out more like the 

 shield of a Lichen, and edged with pink. On making a 

 section through these, numerous transparent linear bodies 

 are seen pressed closely together ; they are composed of 

 minute filaments surrounding a slight column, and termi- 

 nate in several round pellucid lobes. In the round capsules 

 they are also present, and by a gentle pressure under the 

 microscope are seen to issue in numbers from the pore. 



Laurentia is found in perfection from June to September. 



ODONTHALIA. 



This is only found on the Northern coasts of England, 

 Yorkshire, and Scotland. It comes on shore from the deep 

 sea finely dotted with fruit in the month of November. 

 The beautiful stichidia, reddish purple, and the ceramidium 

 both kinds are on this plant. 



BONNEMAISONNIA., 



named after Bonnemaison, a celebrated French Algologist. 

 Nothing can be more graceful and beautiful than this 

 exquisite little plant ; the fronds so delicately ciliated, of 

 a bright rose colour, and dotted all along with tiny cap- 

 sules the true ceramidium; each urn-like vase containing 



