1987] Shat tuck — Pogonomyrmex occidentalis complex 169 
Pogonomyrmex montanus was found to possess states 2 and 3 in 
equal proportions, a finding which agrees with the original 
description (MacKay, 1980). 
Scape 
The scape base of P. occidentalis varies from state 3 to state 5 
(Table 1) but shows no geographic pattern, with the states occurring 
in all parts of the range in roughly equal proportions (Fig. 32). This 
agrees well with the observations of Cole (1968), although he did not 
recognize the extent of the variation. 
All Scape states occur in P. subdentatus (Table 1). States 1 and 2, 
and 90% of the state 3 records occur in western Nevada; state 4 
occurs equally in California and Nevada, and state 5 occurs prima- 
rily in California and Oregon, with a few (14%) records from Nevada 
(Fig. 33). Cole (1968) asserted that the scape base of P. subdentatus 
is equivalent to state 5, and distinct from that of P. salinus. This 
observation was apparently in error because some specimens found 
to have states 1 and 2 in this study were determined by Cole as P. 
subdentatus (specimens now in LACM). 
Cole (1968) describes the scape base of P. salinus as “evenly and 
broadly rounded”, while that of P. owyheei is “not evenly and 
broadly rounded.” Cole’s figures show the scape base of P. salinus 
as evenly rounded dorsally, without any trace of a basal flange, 
while that of P. owyheei has a distinct basal flange dorsally. Two 
aspects of this character are inconsistent with these statements. 
First, the geographic distributions of these character states are not 
concordant with the geographic distribution of the species supposed 
to possess them; and second, material determined by Cole (from 
LACM) does not always possess the appropriate states. 
The geographic distribution of these character states does not 
agree with the distribution of P. owyheei and P. salinus as stated by 
Cole (1968). Scape state 1 (indicative of P. salinus) occurs primarily 
in Nevada, but has also been found at Twin Falls, Montana; Red- 
mond, Cline Falls State Park, Summer Lake, and Hermiston, 
Oregon; and Burlington and Greybull, Wyoming (Fig. 34). Scape 
state 5 (indicative of P. owyheei ) occurs in all areas expected except 
the northwestern portions of its range (Washington, British Colum- 
bia) where only Scape state 3 occurs. Scape state 5 occurs outside 
