48 BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 
Genus CAULORAMPHUS Norman, 1903. 
(For description, see Bulletin 106, U. S. National Museum, p. 174.) 
CAULORAMPHUS POROSUS, new species. 
Plate 33, fig. 17. 
Description .—The zoarium incrusts shells and bryozoa. The zooecia are large, 
distinct, separated by a deep furrow, irregularly elliptical; the mural rim is thin 
flat, finely striated, very little enlarged at the base; the opesium is large of the same 
form as the zooecium. Between the mural rims in the separating furrow' there are 
numerous pores (8 to 10) which are bases of pedunculate and articulate avicularia. 
Measurements .—Opesia 
Tio = 0.40-0.44 mm. 
7o = 0.28-0.32 mm. 
Zooecia 
Lz — 0.60 mm. 
72 = 0.44-0.50 mm. 
Affinities .—It should be remarked that the pores are not arranged on the mural 
rim where the termen is sharp. There are therefore no hollow spines; but they form 
the base, the place of attachment of pedunculate avicularia which surmount them. 
It is therefore in the genus Cauloramphus that this remarkable species must be 
classified. * 
The avicularia being organs of oxygenation w r e suppose that this species must 
live in absolutely calm waters little rich in diatoms. The incessant agitation of the 
mandibles appears to be intended to renew the impure water and to thus carry 
oxygen and nourishment. 
Occurrence. —Pleistocene: Santa Barbara, California (rare). 
Holotype. —Cat. No. 68464, U.S.N.M. 
CAULORAMPHUS TRIANGULARIS, new species. 
Plate 33, figs. 14-16. 
Description .—The zoarium incrusts shells and bryozoa. The zooecia are 
distinct, separated by a wide and deep furrow, elongate, elliptical, with a very short 
proximal gymnocyst; the mural rim is wide, rounded, salient and bears tw'o small 
distal and eight large areal hollow spines placed in the distal half of the zooecium; 
the opesium is elliptical or oval according to the form of the zooecium. The ovicell 
is hyperstomial, globular, ornamented by a semicircular area. In the separating 
furrow with each zooecium there is a small triangular pore which is the base of the 
articulation of a pedunculate and articulate avicularium. 
,, , ~ . \ho = 0.30-0.34 mm. 
Measurements .—Opesia ^ ^ 
mm. 
Zooecia 
i 2 = 0.48-0.52 mm. 
72 = 0.32-0.40 mm. 
Affinities .—The presence of the small exterior avicularium at the line of the 
spines seems to indicate Membranipora ( Cauloramphus) corniculifera Hincks, 1882, 
from the Queen Charlotte Islands. It differs from it in a smaller number of spines 
(less than 18) and in the very different arrangement of distal and areal spines. It 
differs from Cauloramphus spiniferum Johnston in the larger micrometric measure¬ 
ments ( Lz>0A3 mm.), in the presence of less than 12 spines and in the triangular 
form of the pore of the pedunculate avicularium. The two species are evidently 
very close. 
The ancestrular zooecia are smaller than the others. The ancestrula is oval, 
garnished by 12 spines; it engenders three large and three small zooecia. 
