Pacific Salpidae — Yount 
321 
from end of gut projection; larger specimens 
without midposterior tentacle; Sewell (1926) 
and Tokioka (1938) figure those of the small 
individuals as possessing transverse constric- 
tions, as do small POFI specimens, but the 
constrictions are much sparser here; tentacles 
flat at base, filamentous distally, with one 
dorsal ridge, and one ventral ridge which is 
continuous with posterior ridge that fuses 
with its fellow of the opposite side over gut; 
in lateral view, a broad lateral depression or 
narrow groove, ventral to dorsal limiting ele- 
vation, extending from base of tentacle to 
chin, which is smooth in POFI specimens, 
contrary to Sewell (1926, fig. 40) and the 
statement of Thompson (1948: 152); a broad 
ventral elevation extending from chin into 
gut swelling; posteriorly gut swelling forming 
a prominent projection bearing six large 
spines; four symmetrically arranged attach- 
ment organs on each side. The depressions 
and elevations of the test are variable. Muscles: 
Two main masses, of which the first consists 
of M I-II, the second of M III-IV and x; 
first muscle mass interrupted dorsally, second 
forming a distinct joint dorsally, as shown 
by Tokioka (1938); M IV does not help form 
ventral cloacal muscles, contrary to figures of 
Apstein (1904) and Thompson (1948); mus- 
cles extend only a short distance toward ven- 
tral surface. For a complete description of 
mouth and cloacal muscles, see Tokioka 
Fig. 27. Traustedtia multitentaculata, aggregate form, a, Schematic cross section of the test at level of M II; 
b, whole animal, dorsal aspect; c, test, ventral aspect; d, test, right side. 
