492 University of California Publications in Botany [Vol. 8 



9. Microspongium Reinke 



Fronds forming small, cushion-like, rounded, gelatinous masses of 

 various shapes and sizes, composed of a distromatic basal layer the 

 upper cells of which give rise to erect, compact, cylindrical filaments 

 branched or unbranched, among which are intermixed a few hyaline 

 hairs; reproduction by zoospores formed in single (or in seriate?) 

 zoosporangia and by gametes formed in plurilocular gametangia. 



Reinke, Die braunen Algen der Kieler Bucht, 1888, pp. 16 and 20, 

 Atlas, 1889, p. 11, pis. 7, 8, Algenfl. westl. Ostsee, 1889a:, p. 46. 

 Hapalospongidion Saunders, New and little known brown Alg., 1899, 

 p. 37. 



The type species is Microspongium gelaiinosum Reinke. In our 

 judgment there are no fundamental differences between Microspong- 

 ium Reinke (1888, p. 20) and Hapalospongidion Saunders (1899, p. 

 37), consequently we are adopting the earlier generic name. Both 

 genera form diminutive gelatinous cushions and have a distromatic 

 basal disk which gives rise to erect "hairs" and filaments bearing chro- 

 matophores. Unilocular zoosporangia and plurilocular gametangia are 

 present in both, although there are specific differences. In the first 

 place, the erect filaments in Hapalospongidion gelaiinosum are simple. 

 In the second place, the suspected zoosporangia are seriate and inter- 

 calary, probably always so since we doubt Saunder 's statement of their 

 being terminal (in complete filaments). In the third place, the game- 

 tangia are pluriseriate and always intercalary, although there may be, 

 at times, only one sterile, enlarged cell with dense contents at the 

 very apex of the gametangial filament. The arrangement and char- 

 acter of both zoosporangia (if normal?) and of the gametangia 

 resemble those of Pylaiella, but we find similar structures occasional 

 among the Myrionemataceae, but generally on plants showing the 

 terminal types of gametangia. It is for these reasons that it seems 

 best to merge Hapalospongidion in Microspongium. 



Microspong'ium Saundersii S. and G. 



Erect filaments 250-750/* long, embedded in a gelatinous matrix ; 

 cells ii;i the lower part of the filament doliiform, 8-10/* long, 4-5ft 

 broad, in the center of the filament cylindrical, 24-36/i long, 5-6/* 

 broad, in the distal end, 4-5/* long, 7-1 0/x broad ; hairs scattered, one 

 or more millimeters long ; chromatophores discoid ; zoosporangia (?) 



