432 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Length of large specimen (not including branchiae), 60 mm.; 
greatest transverse diameter of same, 9 mm.; length of retracted 
branchiae, 21 mm. 
This species is represented by two female specimens, one col¬ 
lected by Miss Robertson at Port Orchard in June, 1899, the other 
of the same year. 
Although exhibiting great difference as to size — one being more 
than twice the length of the other — they both contain nearly ripe 
ova, indicating sexual maturity. 
The transparent mucous envelope so characteristic of this genus 
was preserved with both specimens. 
by Professor Ritter at Pleasant Beach in May 
Serptjlidae. 
50. Serpula Columbiana sp. nov. PI. 19, ligs. 199-204. 
Form subterete; somewhat flattened dorso-ventrally; gradually 
tapered towards posterior extremity; fecal groove distinct, dorsal 
as far as thorax, there branching and passing to the ventral side 
under the thoracic membrane. 
Thorax with seven setigerous somites, well-developed collarette, 
and thoracic membrane, the latter reaching to the tips of the setae. 
Abdominal somites, 250 or more. 
Branchial filaments 54 on each side, arranged in two spirals 
ascending from the ventral edges, each making a complete turn, 
then extending mesad and meeting each other just over the mouth. 
Branchiae whitish, beautifully banded with scarlet or crimson ; distri¬ 
bution of color variable but usually a broad red band at or near « 
base, followed by two narrow bands, and branchiae broadly tipped 
with the same. Operculum (Fig. 199) on right side, its mate on 
the left very short and rudimentary; funnel-shaped, with about 100 
ribs which form a notched border; deep, funnel-shaped cavity; 
pedicle geniculate just below the operculum. 
Bayonet-setae of first setigerous somite as in Fig. 200; the other 
thoracic setae broadly striate-bordered (Fig. 201). Uncini of 
thorax and abdomen similar in shape, 6-8 toothed; the tip of 
largest tooth often turned outward (Figs. 202, 203). Chisel-shaped 
setae of abdomen as shown in Fig. 204. 
Tube white, calcareous, more or less coiled; anterior portion of 
old tubes often free from the substratum to which tube is attached. 
