lyo] RECORDS OF W.A. MUSEUM. 
CAUDINA TETRAPORA, ' sp. nov. 
Tentacles 15, each with 4 slender, sharply pointed digits, the 
terminal pair the longer. Calcareous ring well developed, about 2 
mm. broad (high) ; posterior prolongations of radial pieces very 
conspicuous, nearly 4 mm. long. Stone-canal single, well-developed. 
Polian vessel single, long and cylindrical. Genital glands rather 
sparingly dichotomously branched. Respiratory-trees very fully 
developed. Body not very stout, passing gradually and not 
abruptly into the tail. The tip of the tail is damaged in both 
specimens, so the condition of the anal papillae could not be deter- 
mined. Calcareous particles knobbed buttons perforated ivith four holes 
and with more or less conspicuous pro- 
jections around the margin (text, fig. I) ; 
they are about .1 of a millimetre long. 
Most of the particles are of compara- 
tively regular form, but more or less 
variation from the typical condition 
may be noted ; buttons with fewer than 
four holes are more frequent than those 
with more. 
Colour white or pale brown. 
Length about 75 mm., of which about 
one-third is tail ; diameter at middle of 
body 15 mm. : diameter near tip of tall, 
about 3 mm. 
Cottesloe Beach, W.A., July 6, 
1912. One specimen. No. 5035. Type. 
Abrolhos Islands, W.A. One speci- 
men, No. 229. 
This species is readily distinguished 
from the other members of the genus 
by its perfectly distinctive calcareous 
particles. It is no doubt most nearly 
related to C. chilensis, the common 
New Zealand species, as might have 
been expected from its geographical 
propinquity. 
Text-Figure i. 
Calcareous particles from body- 
wall of Caudiiia tetrapora. x 350. 
a. A typical button seen from 
the outer surface. 
h. A similar button from the 
side, 
t. A button with long marginal 
projections. 
1 Gr. having four pores, in reference to the calcareous particles 
of the skin. 
