I IO 
Psyche 
[June 
With the dead beetle in its bill, the bird returned to its perch, and 
while holding the beetle against the perch with a foot, proceeded to 
dismember it with the bill. Except for the beetle’s head and perhaps 
a portion of the thorax, no parts were swallowed. The discarded 
pieces were later pecked into various crevices and other hiding places 
in the cage [this behavior has been noted often when captive jays 
are offered noxious spray, e.g. meloid, coccinellid, and lycid beetles 
(Linsley et al., 1961; Eisner, unpublished)]. 
One wonders what would have happened had the secretion hit the 
bird’s eyes. With other arthropods that spray, this has frequently 
been observed, and it invariably has an instantaneous repellent effect, 
leaving the bird partially incapacitated for a time with one or both 
eyes closed, or with the nictitating membranes being drawn back and 
forth over the eyeballs in a quick wiping action (Eisner et al., 1961, 
1962, and Eisner, unpublished). Such birds usually avoid similar 
prey for at least several hours after an encounter. One might argue 
that the jay’s eyes had really been hit by the Chlaenius spray, but 
that they were unaffected by it. It is doubtful, however, that m-cresol 
is harmless. What it does to a lizard’s eye has already been described. 
To our own eyes, even the concentrated vapors are quickly irritating. 
Assuming, then, that the jay’s eyes had indeed been missed, this 
brings to light what may well be a major shortcoming of the beetle’s 
weapon : by aiming the spray against that portion of its body directly 
subjected to trauma, the beetle is likely to miss the eyes of a long- 
billed bird such as a jay, spraying instead the relatively insensitive bill. 
Other arthropods that have been tested (e.g. whipscorpions, Calo- 
soma ) also aim toward the body regions traumatized, but since their 
spray is of greater range and more broadly dispersed than that of 
Chlaenius , the probability is greater that the eyes of the bird receive 
at least a partial dousing (Eisner et al. 1961, 1962). 
2. Versus Abacion. 
The jay promptly pecked and killed the single millipede offered, 
carried the corpse to its perch, and then proceeded to treat it in the 
same way as Chlaenius. No parts were eaten, although a few pieces 
were malaxated in the bill before being dropped. Again as with 
Chlaenius , the discarded pieces were pecked into various hiding places. 
d. Onychomys torridus (Coues) 
1. Versus Chlaenius . 
Two beetles were offered, with identical results in each case. The 
mouse pursued the beetle the moment it was introduced, quickly 
grasped it in its front paws, and with the beetle oriented in such a way 
