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DEPARTMENT OF THE XAYAL .SERVICE 



Thuiaria rohusfa Clark. 



Tropho.some. Stem stout, with deeply cut inter- 

 iiodes; branches also stout, rising from all sides of the 

 stem, dichotomously branched, distally forming a dense 

 tuft; hydrotheca; alternate, not closely placed, almost 

 wholly immersed in the proximal portions, less so dis- 

 tally, tubular; margin bi-labiate; operculum with two 

 flaps on the distal hydrotheca; and one on the proximal. 



Gonosome " Gonangia borne in rows on the ter- 

 minal branchlets, slender, with a terminal collar and 

 aperture and two long curved spines rising from the 

 antero-lateral corners of the shoulders" (Nutting). 



No. 9S. 

 Thuiaria robiintu. 



Thuiaria similis (Clark). 



Trophosome. Colony bilateral, with the stem very 

 distinct "and much stouter than the branches; hydro- 

 thecse sub-opposite, slender, tubular, tapering very little, 

 distal portion free and turned well outward; margin 

 with two distinct teeth; operculum with two flaps. 



Gonosome. Gonangia fusiform, short collar, cir- 

 cular aperture; no spines or annulations. 



No. 99. 

 Thuiaria similis. 



Thuiaria t-nera (Sars). 



Trophosome. Stem slender; branching loose from 

 all sides of the stem ; branches dichotomously branched ; 

 hydrothecse alternate, distant, enlarged above the base, 

 then tai>ered to the margin, one-half free; margin with 

 two blunt teeth; operculum with two flaps or one 

 abcauline flap. 



Gonosome. Gonangia single on the branches, oval, 

 with short collar and wide aperture; no spines or annu- 

 lations. 



No. 100. 

 Thuiara tenera. 



Thuiaria thuja (Linnseus). 



Trophosome. Main stem rigid, not very stout, 

 branches from all sides of the stem, stift", branching 

 dichotomously several times; ultimate branches rigid, 

 distally forming a dense tuft (bottle brush); hydro- 

 thecse alternate, closely placed, almost wholly im- 

 mersed, tubular ; margin without distinct teeth ; oi^er- 

 culum of one abcauline flap. 



Gonosome. Gonangia in rows that may be crowded 

 on the stem and proximal portions of the branches, 

 oval, with short collar and large terminal aperture; a 

 short distinct pedicel; surface without annulations or 

 spines. 



No. 101. 

 TMiiaria thuja. 



