1971] 
Rovner — W olf Spiders 
163 
of the embolus. One interpretation is that the motivation for palpal 
insertion built up under the maximal stimulation of repeated, un- 
successful insertion attempts and that the complete behavior finally 
was released. Theoretical considerations aside, pseudo-insertion be- 
havior may be of interest to workers studying the mechanics of palpal 
insertion in spiders. In a pseudo-insertion the entire genital bulb, 
which is only partly visible when pressed tightly against the female’s 
epigynum during a normal insertion, is brought into view during 
hematodochal expansion and collapse. 
In a previous paper on L. rcibida (Rovner, in press) 1 had em- 
phasized that the palp just used in an insertion was the palp em- 
ployed first in a bout of palpal moistening. The question remained 
as to what aspect of the insertion sequence served as the stimulus 
determining the latter. Three observations in the present study pro- 
vided evidence for an hypothesis: (1) Males lacking one palp moist- 
ened the remaining palp only after insertions or insertion attempts 
with the latter. (2) Males with vestigial palps (lacking genital 
bulbs) did not initiate moistening of these palps after using them 
in attempted insertions. (3) Normal males unable to insert one or 
both palps (due to closure of the female’s copulatory pores) moistened 
the palp just used in an insertion attempt. Apparently the stimulus 
normally releasing palpal moistening was associated with the onset 
of hematodochal expansion, which accompanied the palpal scrape of 
an insertion attempt. (According to Gering, 1953, hematodochal 
expansion is initiated as the palp swings downward at the outset 
of an insertion attempt.) Thus, the proprioceptive stimuli associated 
with the initial phase of an insertion probably were the ones deter- 
mining which palp would initiate the subsequent bout of palpal 
moistening. 
The occurrence in palpless males and males with their palps fixed 
dorsad of cheliceral movements like those seen during palpal moisten- 
ing indicated that the onset and maintenance of this behavioral pat- 
tern did not depend on stimuli resulting from the grasping of the 
palp by the chelicerae. The “chewing” movements occur in vacuo . 
A similar phenomenon was reported in palpless male Linyphia tri- 
angularis (Rovner, 1967). 
Persistence of the pattern of right-left alternation in males unable 
to insert one of their palps suggested that this pattern was not 
altered by the experience of repeated failures on the non-functional 
side. At no point in copulation did males begin to favor the function- 
ing palp by remaining on that side of the female. Males typically 
shifted, however briefly, to the non-functional side, a behavior which, 
in normal males, initiated another palpal insertion. 
