NO. 2 PRE-CAMBRIAN ALGONKIA^T ALGAL FLORA IO5 



Study the semispherical forms are considered as representing a dis- 

 tinct species. Newlandia frondosa (pi. 6) illustrates both the lami- 

 nated and coarsely cellular fomi of growth. Some of its fronds 

 are two feet (60 cm.) or more in diameter with a thickness of 4 

 inches ( 10 cm.) or more. 



The species referred to Newlandia are : 



Nczvlandia concentrica Walcott (pi. 5, figs. 2, 3) 

 Nezvlandia frondosa Walcott (pi. 5. fig- 41 pls. 6-8) 

 Newlandia lamellosa Walcott (pi. 10. figs, i, 2) 

 NcTvIandia major Walcott (pi. 9, fig. 3) 



NEWLANDIA CONCENTRICA, new species 

 Plate 5, figs. 2, 3 



Semisphjerical bodies, built up of concentric layers of irregular 

 thickness that appear to be attached at the base of each cup-shaped 

 concentric layer, and also by irregular projections from the surface 

 of the layers. The layers are perforated to a greater or less extent 

 by irregularly shaped and located small openings. The thickness of 

 the layers varies from 0.5 cm. or less to 2 or 3 mm. The largest 

 individual specimen has a transverse diameter of 9 cm. with a depth 

 of 1.5 "cm. A smaller specimen has a depth of 3 cm. These meas- 

 urements are not very important as the specimens have evidently 

 been somewhat crushed down. 



Observations. — The concentric form of growth of this species is 

 much like the concentrically arranged layers of the nucleus of some 

 of the specimens of A^. frondosa. It differs in having interspaces 

 between the layers and in its more regular form. 



The growth appears to have been about a nucleus around the base 

 of which successive layers were built up. It is anticipated that 

 future collections will afford the material for a more detailed 

 description. 



Formation and Locality. — (400c) Algonkian, Beltian series ; New- 

 land limestone; eastern slope of Big Belt Mountains, 8 miles (12.8 

 km.) west of White Sulphur Springs, at forks of Birch Creek, 

 Meagher County, ^lontana. 



NEWLANDIA FRONDOSA, new species 



Plate 5, fig. 4; plate 6, figs. 1-3; plate 7. figs, i, 2; plate 8, figs. 1-3 



Large frond-like forms built up of thin layers that may have a 



laminated arrangement (pi. 7) or a combined coarse cellular and 



laminated structure (pi. 6). The large fronds appear to have 



