FLORTDEJ2. 277 



Order Rhodomeleae, of which Daaya and Polysiphonia are common 

 genera. 



Order Chylodadiem, represented by only two Californian species. 



Order Sphwrococcoidece, represented abundantly by species Delesserid. 



Order Coralliiiece, containing plants which are remarkable for the 

 large amount of calcium carbonate they contain. Cor<illina is abundant 



Order Gelidiece, represented by Gelidium. 



Order Ifypnete, including only a few species of one genus Hypnea. 



Order Rhodymeniem, of which Rhodymenia and Lomentaria are com 

 mon genera. Rhodymenia palmata, the " Dulse " of our coasts, is used 

 as human food. 



Order Spongiocarp ce, with one species of Polyides. 



Order Squamariem, with one species of Peyssonnelia. 



Order Batrachospermece, to which Nemalion (Fig. 185, B) belongs. 



Order Wrangeliece, with two species of Wrangelia. 



Order Gigartinem, of which Chondrus crispus, the Irish moss so 

 largely used for food, for making blanc mange, etc., is the best-known 

 of the many species on our coasts. 



Order Cryptonemieee, represented mainly on our Southern and Pacific 

 coasts. Schizynemia edulis, of Europe and our Western coasts, is 

 used as human food. 



Order Dumon iece, to which Halosaccion of our Eastern coast belongs. 



Order Spyridiem, represented by Spyridia of our Eastern coast. 



Order Ceramiece. This order contains algae " which are either strictly 

 monosiphonous (i.e., composed of a single tube) and filiform, or which 

 are more simple in their structure than others, approaching in this re- 

 spect the Confervaceae. It abounds in species which display the most 

 exquisite combination of ramification and coloring." A large portion 

 of our marine flora is composed of individuals of this order, as " they 

 abound on our coasts in every little rocky pool, onevery piece of wood- 

 work exposed to the waves, on rocks and stones, and, above all, on the 

 stems of the larger or firmer algae, or even on marine Phanerogams, 

 which they fringe in the most exquisite way with every shade of red, 

 from a bright rose to purple."f 



Lejolisia (A, Fig. 185) and Dudresnaya (Fig. 186) are genera of this 

 order. CallitJiamnion is represented by many species on both our At- 



R 'port of the V. 8. Fish Commissioner for 1875. It is modified from 

 Tluuet's arrangement. The arrangement of the orders and the group- 

 ing of genera into orders are not based upon sexna 1 characters, and con- 

 sequently must be regarded as to a considerable extent artificial. The 

 first-named orders in the list are higher than those that follow. 



f " Introduction to Cryptogamic Botany," by M. J. Berkeley, 1857, p. 

 178. The student is also referred to Harvey's " Nereis Boreali-Ameri- 

 c.ina," a " Contribution to a History of the Marine Algae of North 

 America," published by the Smithsonian Institution, 1852 to 1858. 



