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PACIFIC SCIENCE, Vol. VI, October, 1952 
others have such threads running around the 
entire shell, even on the body whorl, which 
is typically smooth. The transverse ridges 
and nodes are seldom the same in number 
or in size. 
This mollusc was described by Kiener (1834) 
as a separate species, while Stearns (1894), 
Grant and Gale (1931), and others have put 
it into synonymy with Nassartus tegula. In 
my opinion, however, N. tiarula is a sub- 
species of N. tegula. N. tiarula has a more 
southern range than does N. tegula, tiarula 
ranging from Panama to Lower California, 
while tegula ranges from Lower California as 
far north as San Francisco. Also, tiarula has 
a smaller shell and finer sculpture than does 
tegula. The color of the two forms is usually 
different; tiarula is generally white or yellow- 
ish, while tegula is usually purplish brown. 
Of course, variations from the typical form 
of each are often seen, particularly where 
their geographic ranges overlap. 
RECENT GEOGRAPHIC RANGE: Lower Cali- 
fornia to Panama. 
HABITAT: Mud flats or in a few fathoms. 
Nassarius cerritensis (Arnold) 
PL II, Fig. 7 
Nassa cerritensis Arnold, Calif. Acad. Sci., 
Mem. 3: 231, pi. 4, fig. 1, 1903. 
Alectrion cerritensis Arnold, Dali, U. S. Natl. 
Mus., Proc. 51: 576, 1917; Jordan, South. 
Calif. Acad. Sci., Bui. 23: 149, 1924. 
Alectrion {Schizopyga) cerritensis Arnold, Dali, 
U. S. Natl. Mus., Bui. 112: 102, 1921; 
Oldroyd, I. S., Stanford Univ., Pubs., Univ. 
Ser. Geol. Sci., 2(1): 266, 1927. 
Nassarius {Schizopyga) cerritensis (Arnold), 
Grant and Gale, San Diego Soc. Nat. Hist., 
Mem. 1: 675, 1931. 
Nassarius cerritensis (Arnold), Jordan, Stanford 
Univ., Dept. Geol. Contrib. 1(4): 114, 
1936. 
"Nassa ’cerritensis Arnold, Woodring, U. S. 
Geol. Survey, Prof. Paper 207, pi. 35, figs. 
16-19, 1946. 
TYPE specimen: U. S. National Museum, 
No. 162,553 (Grant and Gale, 1931). 
TYPE locality: Los Cerritos (Signal Hill), 
Los Angeles County (Pleistocene). 
DESCRIPTION: Maximum length, 20 mm.; 
average length, about 17 mm.; 7 to 8 some- 
what rounded whorls; several prominent, 
rounded, transverse ridges, not forming 
nodes, crossed by several sharp, raised, spiral 
lines, giving reticulate surface; cancellation 
not as prominent as in N. californianus or 
N. perpinguis; inner lip smooth with thin 
callus spreading somewhat onto body whorl; 
outer lip thickened internally by denticulated 
ridge; sutures wavy; deep groove below body 
whorl; short, broad, recurved anterior canal. 
RECENT GEOGRAPHIC RANGE: Lower Cali- 
fornia to Gulf of California. 
Dali (1917) claims this species is found 
living from San Pedro to the Gulf of Califor- 
nia. However, Burch (1945) says, '’It is a 
common fossil in local Pleistocene deposits 
but seems to be of the southern [Recent] 
fauna. The consensus of opinion regarding 
this species is stated by Dr. George Willett 
briefly, 'Probably lower Californian.’ ” Wood- 
ring (1946) states that, according to numer- 
ous specimens in the National Museum, a 
small race of cerritensis or a closely related 
species is living along the Lower California 
coast at Point Abreojos and Ballenas Bay 
and in the Gulf of California at Guaymas. 
I agree that N. cerritensis does not belong 
to the Recent fauna of the west coast of 
California, although it apparently lives on the 
Lower California coast. I have never found 
any specimens living on our coast, nor have 
I located any specific record of its being taken 
alive on this coast. Statements in the litera- 
ture of occurrences at Long Beach (Grant 
and Gale, 1931) and Santa Monica (Keen, 
1937) probably refer to fossil collections. 
HABITAT: 20 to 30 fathoms. 
Nassarius mendicus ( Gould ) 
PI. I, Fig. 3 
Nassa mendica Gould, Boston Soc. Nat. Hist., 
