SCYTONEMA. 255 



developed from macrogonidia ; figs. 10-11, gonidia devel- 

 oping, producing cysts (figs. 12, 13), with gonidia multiplied ; 

 young plants (fig. 14) in early stage. 



On old wood and rocks around water falls, on mosses, etc., 

 Niagara, N. Y. 



SCYTONEMA CASTELLII, Mass. 



Somewhat pulvinate and pulverulent, soft and porous, 

 widely extended on shelves, walls and flower-pots in a con- 

 servatory. Filaments sparsely ramulate ; aeruginous inter- 

 nally ; distinctly or indistinctly shortly articulate. Sheath 

 close and firm, colorless. 



Diameter of filaments, 8-12 //. 



The many polymorphous varieties of cells, usually con- 

 nected with the development of j&eytonema, were in great 

 abundance with this species. Some are illustrated. 



Plate CLXXXIV, figs. 16-19, normally developed fila- 

 ments ; figs. 20, 21, two older filaments ; the articulations, 

 which are thin discs, 2-4 to a diameter, separate, fall over, 

 and slide out at the broken end ; from these the micro - 

 gonidia are evolved and scattered (fig. 21) ; these enlarge by 

 growth and develop from one stage to another (fig. 23), 

 until a large cyst is reached (fig. 24). This again ejects its 

 contents (fig. 26) ; smaller cells, which grow by the divi- 

 sion of the internal cellules until smaller encysted forms are 

 developed in the maternal tegument, (figs. 27, 28, 29). 

 (Gloeothece- forms). These in turn escape, forming masses; 

 in these masses and from the Gloeothece- forms the young- 

 plants (figs. 30, 31, 32, 33) are developed. 



The Nostov process, shown in part, Plate CLXXXII, figs. 

 8, 9, 10, and Plate CLXXXVII, figs. 30-33, is also evident. 

 Returning, figs. 35-38, are Nostoc-foYms ; figs. 39, 40, young- 

 plants from them. Gloeocapsa cells occur also (fig. 41). 



Whether this is strictly the same plant collected by Mas- 

 salongo in Italy, may be questioned; it is very near it. 



SCYTONEMA MIEABILIS, Wolle. 



Forms small, tomentose tufts on the bark of trees, olive 

 green or brown. Internal trichome aeruginous, cells about 

 half as long as wide, or longer, often torulose ; sheath wide, 

 light or dull yellow. Pse?wZo-brauchlets usually in a man- 

 ner geminate ; making the usual fold in the sheath and 

 pressing through, it does not rupture in the usual manner, 



but the two grow unitedly to considerable lengths, produc- 

 17 



