HOW TO KNOW THE SEAWEEDS 



44a Young growing points with short or long deciduous hairs around 

 the apical cell. Fig. 72 Chondria (in part) 



Fig. 72. Chondria tenuissima (Goodenough & 

 Woodward) C. Agardh. 



A small portion of a plant to show the 

 branched, deciduous hairs aggregated around 

 the growing apices and the spindle-shaped 

 branches. X 5. This is the coarser of the two 

 common species of Chondria with emergent 

 apices along the Atlantic coast as far north as 

 New England. Two other species occur north 

 of New Jersey, several to the south of North 

 Carohna, and two species are abundant in 

 southern California. They vary from quite deli- 

 cate plants with main axes less than V2 mm. 

 thick to quite large, coarse plants 25 cm. tall 

 with axes 2 mm. thick. 



Figure 72 



44b Young growing points without deciduous hairs especially aggre- 

 gated around the apical cell. Fig. 18b 45 



45a Medulla, especially the outer medulla, with slender, rhizoidal 



filaments packed between the larger medullary cells. Figs. 73,74. 



Gelidium (in part) 



B 



Figure 73 



Fig. 73. Gehdium crinale (Turner) Lamouroux 



Transections of parts of two different plants to show (A.) the ag- 

 gregation of rhizoidal filaments in the central region of the medulla, 

 and (B.) the aggregation in the outer region of the medulla. The latter 

 is the more common situation encountered in Gehdium. This is a 

 rather small, tufted plant reaching 5-7 cm. in height along both the 



63 



