712 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



The californica of d'Orbigny was placed by him in the genus Uni- 

 cavea, which indicates that his species has uniserial rays. On the other 

 hand the californica of Busk, Gabb and Horn, Waters, and Robertson 

 is definitely stated to have biserial or triserial rays and has been rede- 

 scribed as Lichenopora buskiana by Canu and Bassler, 1928:164. The 

 description of the zoarial form by d'Orbigny might apply to numerous 

 species, but his final statement of the large size of the cancelli is more 

 definite and is an exact statement of their nature. In older colonies the 

 cancelli become partially closed by an "iris-like" thickening of the in- 

 ternal wall, but the outlines of the large pores are evident in the raised 

 separating ridges. Moreover, the species is common in the area where 

 d'Orbigny obtained his material. Lower California, and we are fortunate 

 to have ten specimens from three stations in Santa Maria Bay and 

 Magdalena (Madelaine) Bay, that is, in the type locality of californica. 

 It appears very probable, therefore, that after a century d'Orbigny's 

 species has been resurrected. 



The zoaria are round, low dome-shaped with the central area flat or 

 somewhat depressed in the young. The colonies are all small, not over 

 4 mm in width, the central area one-fourth to one-third as wide as the 

 zoarium ; the radiating rows of tubules are all definitely uniserial, about 

 10 primary rows with shorter ones between them toward the margin. 

 The peristomes are only moderately elevated, slightly higher toward the 

 central area, connate to their tips which usually are truncate but some- 

 times are extended into short points on their distal borders; the aper- 

 tures are slightly elongated in the direction of the rays, about 0.10 mm 

 long by 0.08 mm wide. The cancelli of the central area are noticeably 

 larger than the tubules, the apertures round and as much as 0.13 mm 

 in diameter, partially closed by the characteristic "iris" diaphragm; the 

 pin-head spicules are abundant. Between the rays there are two rows 

 of cancelli, occasionally only one, which are somewhat smaller than at 

 the center. 



The brood-chambers are interradial or extending somewhat into the 

 central area, the roof a thin calcified membrane with minute pores, 

 later covered by secondary cancelli of the usual type. The ooeciostome is 

 short, round, thin-walled and a little larger than the zooecial apertures. 



There is a peculiar type of zoarial budding which I have not seen 

 described and which I have observed in only one other species, D. 

 alaskensis new species, described in this report. The sub-colonies arise 

 on the frontal side toward the margin but do not extend beyond it and 

 in the three colonies at hand they are exactly similar in origin. When I 



