ULOTHRIX. 133 



garis ; with this species there often occur such filaments as 

 figs. 14-17. First specimens seen were a puzzle to me and 

 suggested names for new species of Hormospora, but 

 repeated observations removed all doubt concerning the 

 unity of the species ; these are not stages of development, 

 but different forms approaching decay. 



Plate CXXIV, figs. 10-16, are parts of filaments of similar 

 character, green cells dividing not only in one, but some- 

 times in two directions. Figs. 17-20, a very distinct form, 

 purplish red, or reddish brown, vely gelatinous ; found in 

 quantity sufficient for mounting nearly two hundred cards ; 

 in pool, Bethlehem, Pennsylvania. Many of the cells 

 elongate laterally as in an early stage of growth, others 

 divide transversely making short, lateral series. Unlike 

 any known form ; and as all the filaments are apparently of 

 nearly the same age, it was impossible to trace a positive 

 relationship to either Ulothrix or Conferva, but there is little 

 doubt they are merely a condition of one or the other. The 

 plant in its present condition has the appearance of a small 

 form of Bangia, but can not reconcile it to that genus. 

 Diameter of gelatinous sheath, 15-17 ^ ; of cells, 7-8 /*. 

 Figs. 21-23, same plate, yet another Hormiscia-likQ form, 

 also red, or reddish brown, found on damp forest ground in 

 Vermont. The cells primarily green, then yellow, then 

 reddish brown ; evidently not a vegetative condition, or a 

 normal form, but what it really may be, remains for future 

 observers to determine ; perhaps merely a Zygnema. 



Diameter of sheaths, 25-30 //. 

 Diameter of cells, 15-17 yw. 



Genus 25, ULOTHBIX, Kg. 



Filaments simple, articulate; articulations short, more fre- 

 quently shorter than longer than the diameter ; cell membrane 

 thin, often very thin, very rarely lamellose. Cell contents green, 

 effused, or parietal, inclosing an amylaceous granule. 



Propagation by macro- and microzoospores. Copulation of 

 the latter has been observed in U. zonata ; both are set free by 

 the breaking of the walls of the mother cell. 



ULOTHRIX ZONATA, (W. and M.) Aresch. 



Eather bright green, mucous, from 2-3 inches to two feet 

 in length , in vegetative state always attached ; sterile cells 



