144 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



cruciate or zonate, usually collected in nemathecia or in superficial spots 

 (sori), sometimes scattered ; cystofcarps composed of numerous masses 

 of irregularly placed spores, between which are found portions of the 

 tissue of the interior of the frond, the whole sporiferous mass being 

 covered by the swollen surfaces of the frond, which are sometimes raised 

 in subspherical conceptacles ; spores discharged through special car- 

 postomes. 



A large suborder, comprising species which are sometimes more or less cylindrical in 

 shape, but which are more frequently expanded and of a coarse, subcartilaginous con- 

 sistency. Some of the largest Floridece are found among the Gigartinece, and perhaps 

 no other suborder contains so many ill-denned species as the present. Owing to the 

 thickness and opacity of the fronds, the study of the development of the cystocarps is 

 attended with very great difficulty, and as yet no full account of the formation of 

 the fruit of any of the species has been published. In the Notes Algologiques, Bornet, 

 however, gives a brief account of the formation of the cystocarp in Gymnogongrus 

 patens. In all the species the spores are irregularly grouped in several distinct masses, 

 which are imbedded in the tissue of the frond, the cells of which undergo a change as 

 the spores ripen, their walls becoming thick and lamellated, and traversed by numer- 

 ous small canals. In Callophyllis and some other genera the sporiferous mass and the 

 enveloping tissue of the frond form subglobose swellings external to the surface of the 

 fronds, but iu other genera, as Gymnogongrus, the sporiferous mass occupies the central 

 part of the frond, which swells on all sides. The cystocarps discharge their spores 

 through carpostomes or narrow canals formed in the cortex of the fronds. Sometimes 

 there is a single carpostome, but iu some genera, as Gymnogongrus and Ahnfeldtia, there 

 are several. 



1. Fronds terete 3 



2. Fronds compressed 4 



3. Substance rigid, horny Ahnfeldtia. 



Substance soft, succulent , Cystoclonium. 



4. Fronds thin, leaf-like Phyllophora. 



Fronds cartilaginous or subcartilaginous 5 



5. Cystocarps external in special leaflets Gigartma. 



Cystocarps immersed 6 



6. Central part of frond composed of roundish polygonal cells. 



Gymnogongrus. 



7. Central part of frond formed of slender anastomosing filaments. 



Chondrus. 



PHYLLOPHORA, Grev. 



(From QvTiAov, a leaf, and <pepu, to bear.) 



Fronds stipitate, stipes expanding into a rigid-membranaceous, flat, 

 simple or cleft lamina, proliferous from the disk or margin, composed 

 internally of oblong polygonal cells, with a cortical layer of minute, 

 colored, vertically seriated cells ; autheridia contained in small cavi- 

 ties ; tetraspores cruciate, arranged in moniliform filaments, which are 

 packed together in external excrescences (nemathecia) ; cystocarps ex- 



