i Birotulata new genus. 



>lony flabellate. Both nodes and internodes traversed bj water-vascular canals. The 

 ill lm: ik- on the nodes. Characteristic spicules doublé wheels. 

 |\|.i- sp( tulata splendens Nutting. 



i. /.'.•;■ splendens new species. Plate X, figs. 1, ia, 2\ Plate XII, fig. 



Stal I ual Anchorage, Kei [slands. 22 meters. Lithothamnion, sand .nul coral. 



The type was originally a very large colony, bul has been broken ihto many fragments. 



1 cimen was flabellate in form and not reticulate and probably originally measured as 



much as 1 meter in height. The trunk and main branches are laterally compressed, the former 



m. X i-9 cm. in section, and the latter as much as 2.8 cm. ;,-; 2.2 cm. in section. 

 Ihc main stem bifurcates 7 cm. from its proximal end into two very unequal branches. The 

 r <>l" these, afin- giving off tour branchlets, the stulis of which remain, bifurcates into two 

 branchlets which are approximately round in section, the larger one having a diameter of 2 cm. 

 Some <>( the more distal branchlets are round and others slightly compressed laterally. The 

 branching is in part dichotomous and in part lateral, the tonner prevailing in the distal parts 

 of the colonv. the ultimate branchlets being [.5 mm. in diameter. The furcations are usually 

 U-shaped rather than Y-shaped. The calyces are on the sides and front of the colony, leaving 

 a bare posterior space, sharply distinguished by its bright chrome yellow color, as il' the colony 

 were crudely painted scarlet on front and sides and yellow behind. 



The individual calyces are closely set and have each a broad border of scarlet which 

 gives the red color to the branches. They are almost entirely included and very small, not 

 being over .5 mm. in diameter on the average. Their walls, like the general ccenenchyma, art; 

 filled with small smooth double-wheels. The polyps are retractile, and bear a collaret which is 

 rather strong and composed of two or three rows of transverse red spindles. Above these a 

 few spindles are arranged en chevron on each tentacle base, and beyond this the spindles 

 are longitudinal. The nodes are not indicated superficially on the main stem and larger branches, 

 and are nowhere so conspicuous as in Melitodes ochracea. The internodes, as well as the nodes, 

 are penetrated by numerous water vascular canals. 



Spicules. The most conspicuous and numerous forms are the double-wheels charac- 

 teristic of the- genus. These are on the surface and also constitute the chicf element in the 

 ccenenchyma. They lonk much like two huns pressed together, sometimes unsymmetrically. Some 

 <>f them have a small nodule at each end in addition to the two wheels. rhere .we also densely 

 rculate short stout spindles, and ordinary spindles, mostly from the polyps, and numerous 

 ilar forms which are usually minute. The spicules of the axis are smooth bar-like and 

 He- Üke forms. 



lor. The colony is scarlet and chrome yellow, the posterior face of the distal parts 

 ny being sharply differentiated, as il painted with vivid yellow. The yellow shows 



