1973] 
McCluskey — Generic Diversity 
299 
and Williams’ (1956; cf. Batschelet 1965, but only for a two- 
sample case) test: if the samples are considered random, F ql N _ q — 
[ (N-q) (2R-R) ] / [ (q— 1 ) (N-2R.) ] = 3.58 and P ’<f.05 
[N = 33 (species), q — 4 (genera), R. refers to the combination 
vector for all the species in each genus, and R refers to the com- 
bination vector of all genera] . 
Figure 2 shows that for the three genera of this tribe with enough 
species records, the flight hours of the species within a genus are 
strikingly similar, exceptions being the one morning species of Lasius 
and the two afternoon species of Formica. Comparison of the flight 
hours by the Watson and Williams test again shows the likeness 
within genera to be greater than that between genera (P < .001). 
It seems noteworthy that a single rhythm character would char- 
acterize a genus this well. A preliminary test for generality of the 
within-genus likeness of flight hour was made on eleven genera from 
five subfamilies of ants (all of those from which literature records 
of at least three species per genus were at hand). The Watson and 
Williams test gives a value of P < .001 ; this is true also if the three 
formicine genera are omitted and only the other eight considered. 
By including all species records no matter what tribe, it is pos- 
sible in a few cases to rank workers from early to late within each 
given locality (McCluskey, unpublished). Again species appear 
grouped generically, giving further suggestive evidence of a taxo- 
nomic or historical explanation of the phase differences (as opposed 
to a strictly ecological or geographical explanation). 
An example of a physiological character earlier shown to correlate 
well with a previously-established classification is that by Priesner 
(1968). Male moths throughout the family Saturniidae were shown 
to react to pheromone from the females in a manner roughly cor- 
responding to taxonomic grouping. 
It should be added that some of the phase relationships considered 
here might in fact be explained by response to temperature, since 
these are records from the field rather than a constant temperature 
laboratory. But this consideration does not change the fundamental 
nature of the conclusion drawn. Further, certain ants which have 
been studied in constant temperature exhibit a phase relationship to 
the light cycle similar to that in the field (McCluskey 1963, 1965, 
1969; McCluskey and Carter 1969). 
Summary 
Literature records of field mating flight and worker rhythms in- 
dicate the phase to be much more alike from species to species within 
