88 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



R. clavata, (Oarm.) Crouan, Florule du Finistere. (Myrionema clava- 

 turn, (Jarin., in Phyc. Brit,, PI. 34S.> 



Fronds thin, forming closely adherent crusts or coriaceous expansions, 

 at first orbicular and afterwards irregular ; paraphyses clavate, rather 

 uniformly diffused over the frond; unilocular sporangia pyriforni, 

 .06-7 mm broad by .15-.18 mm long, attached to the base of the paraphyses. 



On stoues and wood work 



Eastport, Maine ; Wood's Holl, Maiden, Mass. ; Europe. 



A small species, whose position is doubtful. It was placed, by Harvey in Myrionema, 

 from the typical species of which ic (lifters in having a frond composed of several 

 layers of horizontal cells. By Crouan it was placed in Ralfsia, but the erect fila- 

 ments rather resemble the paraphyses in Myrionema. Iu sbort, the species may be said 

 to be a Ralfsia with diii'use fructification and slightly developed frond, or a Myrionema 

 with an excessively developed basal portion. American specimens resemble perfectly 

 the No. 56 of Crouan 's Algues Marines du Finistere. The alga described by Areschoug 

 under the name of Lithoderma fatiscens bears a striking resemblence to the present 

 species. The species is much smaller and thinner than R. verrucosa, not exceeding on 

 the average . 15 mm in thickness, and covers stones and wood work at Eastport, some- 

 times in company with R. verrucosa. Further inquiry will probably show that the 

 plant is common along the whole coast. 



Family ASPEROCOCCE^. 



Fronds tubular or compressed, usually simple, occasionally branched ; 

 fructification in external scattered sori, composed of cylindrical few- 

 celled paraphyses and spherical unilocular sporangia. 



ASPEROCOCCUS, Lam. ' 



(From asper, rough, and kokkoc, a berry.) 



Fronds olive-brown, simple or branched, hollow, composed of a few 

 layers of cells, those of the interior being larger and colorless, those of 

 the surface smaller and colored; fruit external, scattered in spots (sori) 

 over the fronds ; sori composed of paraphyses and unilocular sporangia, 

 which are formed from the superficial cells of the fronds ; paraphyses 

 numerous, cylindrical or club-shaped ; unilocular sporangia globose, ses- 

 sile between the paraphyses ; plurilocular sporangia unknown ; hairs 

 tufted, arising from the superficial cells ; growth of fronds basal. 



The genus Asperococcus is distinguished by the external scattered fruit, consisting of 

 paraphyses and unilocular sporangia. In the Nereis Am. Bor. it was placed by Harvey 

 iu the order Dictyotacece, but the fructification in that order is now known to be very 

 different. The genus comprises a small number of species, which are widely diffused, 

 although as yet only one has been found on the New England coast. The Aspcrococci 

 resemble, to a certain extent, species of Rhyllitis and Scytosiphon, but are easily dis- 

 tinguished by the fruit, which is almost always present. Plurilocular sporangia .are 

 unknown in the true Asperococci, and the old A. sinuosus, which is found in Florida 

 and California, is considered by Bornet to belong to the genus Hydroclathrus, which 

 has plurilocular sporangia of the same type as PhyUitis and Scytosiphon. A. compressus 



