522 BULLETIN OF THE BUREAU OF FISHERIES. 
Cryptonemia crenulata J. Agardh. PI. CXIII, fig. 3. 
Cryptonemia crenulata, J. Agardh, 1847, p. 11. 
Cryptonemia crenulata, Harvey, 1853, p. 184. 
Acrodiscus ? crenulatus, De Toni, 1905, p. 1599. 
A. A. B. Ex. No. 23. 
P. B.-A. Nos. 549, 2100. 
Frond flattened, ruffled, 2 to 14 cm. tall, 0.5 to 5 cm. wide, supported on a short stipe, which soon 
passes over into the expanded portion of the thallus, branching dichotomous or almost palmatifid, often 
with similar expanded, dichotomous proliferations from the margins, margin sometimes entire, usually 
eroso-denticulate and slightly curled, segments linear or wedge-shaped, rounded, obtuse, or truncate at 
the apices; tetrasporangia occurring in rounded sori near the margins of the segments; cystocarps 
appearing as minute dots, scarcely visible to the naked eye, clustered here and there on the surface of 
the frond; texture membranaceous, rigid; color rosy purple, sometimes slightly greenish. 
North Carolina to Brazil. 
Occasional on Bogue Beach, Beaufort, N. C., August to October, sometimes bearing cystocarps. 
This species was removed from the present genus by De Toni and doubtfully placed under Acro- 
discus Zanard. with the note that, according to the suggestion of Schmitz, the latter genus should be 
united with Polyopes J. Ag. The structure of the cortex of this species is, however, parenchymatous, 
agreeing with that of Cryptonemia lomation (Bertol.) J. Ag., the type of the genus, and is not composed 
of anticlinal rows of cells, as in Acrodiscus and Polyopes. The species is accordingly retained under 
Cryptonemia. 
This species is easily recognized by the crisp, ruffled frond, which is so rigid that it can be made 
to lie flat only by considerable pressure. Dried specimens, when moistened, show this character almost 
as clearly as do living plants. 
This is the northern known limit of the species and of the genus. 
Family 2. CORALLINACEZ (Gray) Harvey. 
Frond extremely various inform, filamentous, foliaceous, crustaceous, flattened, terete 
or irregular, simple or dichotomously, laterally or irregularly branched in various ways, 
sometimes endophytic, nearly always more or less strongly incrusted with lime, structure 
cellular-filamentous, nearly always compact; tetrasporangia (or sometimes disporangia) 
occurring in more or less well-defined sori embedded in the thallus, sometimes in definite, 
flask-shaped conceptacles scattered over the frond or borne in special, swollen portions, 
often mingled with sterile paraphyses, usually zonately divided, sometimes forming only 
two spores, communicating with the exterior by one or more pores; antheridia borne in 
flask-shaped conceptacles formed in the thallus and communicating with the exterior 
by a pore, scattered over the frond or borne in special swollen portions, forming sper- 
matangia singly on long stalks or in chains, mingled with paraphyses; carpogonia and 
auxiliary cells numerous, usually borne together on upright, branched filaments arising 
from the base of flask-shaped conceptacles formed in the thallus and communicating 
with the exterior by a pore, scattered over the frond or borne in special swollen portions, 
gonimoblasts numerous, usually arising as single cells from the periphery of a large 
discoid cell in the base of the conceptacle, formed by the fusion, after fertilization, of ali 
the auxiliary cells, cutting off chains of carpospores in basipetal succession, the numerous 
carpospores and parphyses finally filling the conceptacle. 
Nearly 400 species, widely distributed, mostly in warm seas. 
KEY TO GENERA. 
a.,, Phallus;consisting. of a, flapdisks, sancvap/c-cacene AJ etsy e +5 - sd Foes » belts soup dasietiaae «aaa b. 
6. Thallus, thin, composed of a single undifferentiated layer. .. : .1. Melobesia (p. 523). 
6b. Thallus thick, composed of a thin lower layer and a thicker ere layer, tetra- 
sporangia borne on the sides of the conceptacle.................... 2. Dermatolithon (p. 524). 
