254 University of Califorma Publications. | ZOOLOGY 
tending upward, arising from a definite chamber just above the 
lateral avicularium, the chamber projecting somewhat and being 
not quite circular especially as seen from the dorsal side (fig. 
PA Gh): 
This species is abundant at Orea, Prince Williams Sound; 
reported by Hineks from Cumshewa Harbor, Queen Charlotte 
Island. 
7. Menipea occidentalis Trask. 
Pl. VI, figs. 22, 23, 24, 25. 
Menipea occidentalis Trask, 1857, p. 113, PISA, hip. 
Menipea compacta Hincks, 1882, vol. 10, p. 461. 
Menipea compacta Hincks, 1884, vol. 13, p. 208, Pl. LX, fig. 8. 
Zoarium forming bushy tufts from 15 to 50 mm. in height, 
attached by a large number of root fibres. Root fibres not de- 
veloped throughout the colony, this species being in no sense a 
climber. Branching extremely regular and characteristic (fig. 
22), each tuft or frond consisting of a main rib or primary 
branch (pr. br.) from which secondary branches arise alter- 
nately (sec. br.), these again giving off tertiary branches (ter. 
br.). Internodes consisting of three zocecia (fig. 23). Joints (j.) 
yellow or brown arising from definite chambers on each side of 
the most anterior zocecium of an internode. Zoawcia elongated, 
narrowed below; aperture (ap.) occupying about half the front. 
surrounded by six jointed spines, sometimes by five or seven; 
two arising on the margin of the upper half of the aperture 
opposite each other and meeting across it (c. sp.) ; two other 
longer ones extending from the upper margin of the aperture 
(u. sp.), and between these two and the two crossed spines, two 
other opposite flaring spines (fl. sp.) ; on the terminal zocecia 
these flaring spines often grow very long so that each zocecium 
is then bordered anteriorly with a bristlng array of four long 
spines. Scutwm (sc.) sometimes a mere spine, sometimes broader 
than a spine, arising on the lower half of the inner margin of 
the aperture. Avicularia large, lateral, sessile, found typically 
on all the zocecia except the one at the bifurcation of a branch. 
Frontal avicularia wanting. Oa@cia usually developed on the 
tertiary branches, large, globose, covering the zocecial wall below 
