1974 ] 
Coyle — Genus A liatypus 
437 
Methods 
COLLECTING METHODS 
Because of their covert behavior, A liatypus spiders are rarely col- 
lected except when one concentrates on special collecting strategies. 
Banks and slopes of promising habitats (to be described thoroughly 
in a paper on A liatypus natural history) are best searched in daylight 
by carefully examining suitable microhabitat surfaces for the out- 
line of a closed trapdoor. However, whenever the trapdoors are 
sealed, such as during dry periods, they may become covered with 
loose soil particles or other debris; carefully shaving away the top 
layer of soil may then be the only way to locate burrows. Night 
collecting is usually less satisfactory than daytime collecting since 
even unsealed Aliatypus doors are only cracked open at night and 
not easily located with artificial light. At night it is sometimes pos- 
sible to trap active spiders at their burrow entrances by thrusting a 
knife blade into the soil and across the burrow lumen just below the 
spider, but frequently the soil is too hard. More information can 
be gained by careful excavation of the burrow in daylight. An army 
trench shovel, a small, chisel-head, rock hammer, a large pocket knife, 
and pruning shears are all useful for excavating in the often hard 
and root-bound soil. Penultimate males, easily recognized by their 
swollen pedipalpal tarsi, will often molt to adulthood if kept in a 
cool, humid, and dark environment. Just before and during the 
mating season (usually during the wet fall and winter months) 
recently matured males may be found in their burrows prior to 
abandoning them. Wandering males are best collected at night by 
hand or with pitfall traps in dense burrow aggregations during opti- 
mum mating weather. 
ANALYSIS OF VARIATION 
I have examined the taxonomy of Aliatypus by means of an analy- 
sis of variation nearly identical to the analysis employed in my re- 
visions of Antrodiaetus (Coyle, 1971) and Atypoides (Coyle, 1968). 
Such an analysis largely overcomes difficulties posed by the relatively 
simple reproductive anatomy, by the instar heterogeneity of adult 
female samples, and by heightened geographic variation, difficulties 
which appear to be common to most mygalomorph spider taxa. The 
material analyzed consists of 252 adult females and 78 adult males. 
The sample size for each species is indicated in Tables 1 and 2. 
Initially, variation in a large number of qualitative and quantita- 
tive characters was briefly surveyed, and from these characters the 
diagnostically most promising were selected and their variation studied 
