88 MARINE 



set at acute angles, giving the plant a slender appearance ; color black 

 or dark brown. It is common on the California coast. (Plate XXVI.) 



P. Jiaileyi. Frond three to six inches high, flat; branches emanate 

 from edges of the flat stems ; main branches wide- spreading and irregularly 

 placed, secondary branches regular and alternate ; branchlets one eighth 

 to one half of an inch long, covered on the edges and around the top 

 with incurved ramuli ; branchlets broken off near the base of the 

 branches in mature plants ; branchlets usually uniform in length, but 

 occasionally one is longer and branches like the primary stem ; color 

 black. Common on the California coast. 



P. Harveyi. Frond two to six inches high ; grows in globose tufts, 

 and has a bushy aspect ; branches stiff and wide-spreading ; stems and 

 branches beset with simple or branched spine-like branchlets ; color 

 dark brown, or black when dry ; does not collapse when taken from the 

 water ; cystocarps on short stalks ; siphons four in number. It grows 

 on eel-grass and algae, and is common in Long Island Sound and north- 

 ward. Called locally niggerliair. (Plate XXVI.) 



P. Olneyi (dough-balls). Fronds two to five inches high, densely 

 tufted ; soft filaments of hair-like fineness, much branched, and spread- 

 ing ; when in fruit covered with tiny balls or cystocarps ; siphons four 

 in number. It is common from Cape Cod to New York. 



P. fibrillosa. Frond four to ten inches high, rather robust below ; 

 main stem quickly lost in a number of prominent stems and spreading 

 branches ; irregularly and profusely branched, becoming ultimately very 

 fine ; numerous branchlets covered with colorless fibrils in hairy tufts, 

 which give it a misty appearance ; fibrils so delicate that they do not 

 show well in dried specimens, but a distinct feature by which to recog- 

 nize the species in the young plant; color light to dark brown; cysto- 

 carps adherent to branchlets or on short stalks ; siphons four in number ; 

 main branches only corticated. It is common in summer on stones and 

 on eel-grass, at low-water mark, from Cape Cod to New York. (Plate 

 XXVII.) 



f. violacea. Fronds six to twenty-four inches high, pyramidal in 

 general outline ; main axis with long, wide-spreading branches at the 

 base ; branches rather robust and naked below, but numerous and be- 

 coming very fine and tufted at top ; cystocarps adherent or on short 

 stalks ; siphons four in number ; main stems corticated ; ultimate 

 branchlets show articulations ; color brownish-red. It is common from 

 New York northward. (Plate XXVII. ) 



P. urceolata. Frond three to ten inches high ; main stem bristle- 

 like ; branches naked below, divided and subdivided above ; branches 

 with short branchlets set at a wide angle and often recurved ; siphons 

 four in number ; shows articulations ; color deep red. Name refers to 

 cystocarp, which resembles a pitcher. The plant grows in loose tufts, 

 and is common from New York northward and on the California coast. 



Variety formosa. Filaments soft and finer than in P. urceolata ; 

 branches long and flexuous ; articulations five to ten times longer than 

 broad ; color bright red. It grows in tufts sometimes a foot long, and 

 is found only in the spring. 



P. variegata. Fronds four to ten inches high ; filaments thick as a 

 bristle below, and branched in a forking manner to the very top ; 

 divided at long intervals below, at the top becoming of hair-like fineness 



