54 



MEMOIRS or THE NEW YORK BOTANICAL GARDEN 



but more or less scattered, tapering to blunt apices; trichomes 

 1-3 in a sheath, jjale aeruginous, slightly constricted at the cross- 

 walls, 2.4-2.8 M diam. ; cells quadrate to two times as long as the 

 diameter, finely granular, apical cell blunt-conical; sheath 2-3 

 times as thick as the trichome, rose-pink in color. 

 Growing on red earth, Mayagiiez, no. 880 c, type. 



MicROCOLEUs sociATUs minor var. nov. 



Filaments more or less intertwined into small fascicles, 1-1.5 

 cm. long, erect or mostly prostrate, forming a loose pannose 

 stratum ; trichomes single within a sheath, 2.4-2.7 \\ diam., yel- 

 lowish green, apical cell acute-conical. 



Habitat unknown ; si3ecimen in the Herbarium of The New 

 York Botanical Garden, collected in the Luquillo Mountains, 

 Porto Rico, and determined by Hauck as Scytonema tlielepJioroi- 

 des Mont. 



The variety minor differs from the species in being longer, in 

 having smaller trichomes, and acute-conical apical cells. 



Inactis ecalcarea sp. nov. 



Plate 11, figure 100 



Filaments standing parallel and erect, forming with Calo- 

 thrix a velvety stratum ; trichomes 0.9-1.1 n diam., 1-4 in a 

 sheath, straight, not tapering, not constricted at the dissepi- 

 ments ; cells quadrate, pale, aeruginous ; cross-walls very thin ; 

 aj^ical cell blunt ; sheath very obscure. 



Growing on stones in the Turabo River, near Caguas, no. 

 481 a, type. 



The material used as the basis of this species is clean and 

 in good condition, and free from lime, the presence of which is 

 rather common in the genus. 



LYNGBYOPSIS gen. nov. 



Filaments prostrate, composed of one or more multicellular 

 trichomes, each developing its individual sheath; false branch- 

 ing in either or in both directions towards the ends of the longi- 

 tudinal axis ; sheath firm and membranaceous. 



The genus Lynghyopsis, as proposed here, seems most closely 

 related to the genus Hyphcothrix. It is to be distinguished by 

 its method of branching combined with the character of the 



