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PACIFIC SCIENCE, Voi. XXII, April 1968 
tions, although there is a tendency Germany 
> Siberia > St. Matthew in regard to lengths 
of outer setae, endopods, and inner spines. The 
German animals had particularly short furcal 
rami and long inner terminal setae. The Ger- 
man population has a quotient > 1 for inner 
seta ramus (panel D, Fig. 19) suggesting 
that the lengths of these structures do indeed 
differ from those of the other populations. There 
are a number of indications that the Siberian 
C. kolensis is similar to the Pt. Barrow speci- 
mens and to a lesser extent to the St. Matthew 
forms (Table 3 and 4, Fig. 18). 
To further assess the variation shown by the 
five populations, six measurements were sub- 
jected to one-way analysis of variance. The 
results (Table 5) show that two values (lengths 
of furcal rami and outer spine) are significantly 
different at the .01 level and that the endopod 
lengths differ significantly at the .05 level. In- 
spection of Figure 18 suggests that much of the 
variation in furcal length may be due to the 
German animals. Analyzing furcal length after 
omitting the German specimens resulted in an 
F = 4.63, not significant at the .05 level. Like- 
wise if the St. Matthew 809 animals are omitted, 
the F value for the outer spine length is not 
significant at the .05 level. 
Along with the specimens from the Marsh 
collections, the U. S. National Museum also 
loaned three specimens of C. kolensis from Lake 
Wigry, Poland, identified by Kozminski. Char- 
acteristics of the terminal seta, endopod, and 
rami of these animals are closer to those of the 
German specimens than they are to the Alaskan 
animals (Tables 3 and 4). The length of the 
abdominal segments (post genital) is 121% of 
the furcal length. 
In attempting to summarize the morphological 
variation shown by these populations, the Ger- 
man animals appear to possess long inner setae 
and short furcal rami, resulting in only the inner 
Fig. 18. Comparison of measurements of Cyclops kolensis from various populations. A, Length of seg- 
ment 3, endopodite, leg four; B, length of inner terminal spine of segment 3, endopodite leg four; C, length 
of outer terminal spine of segment 3, endopodite, leg four; D, length of furcal ramus; E, length of inner ter- 
minal seta of ramus; F, length of outer terminal seta of ramus. Values in microns; thin vertical line is the 
range, heavy vertical line is the 90% confidence limit and horizontal bar is the mean. 
Populations: a, Pt. Barrow, Alaska; b, Siberia (Rylov 1948) ; c, St. Matthew Island, Alaska (coll. 814) ; 
d, St. Matthew Island, Alaska (coll. 809); e, Grosser Ploner See (Herbst 1955); f, Canada (Marsh collec- 
tions, U. S. National Museum) ; g, Lake Wigry, Poland (Kozminski collections U. S. National Museum). 
