Figure 10-2. Diagram of Stimulation-Recording 
Chamber (“Olfactometer"). 
NOTE: Stimulus is injected with a syringe (A) into a seawater flow (B) over 
the dissected lobster antennule. The antennule is perfused through a micro¬ 
pipette with oxygenated lobster saline (C) which exits the antennule into a 
bath of saline (D). To make recordings, one small bundle of nerve fibers is 
lifted from the saline bath into the air with a platinum hook electrode (E). 
Seawater and saline baths are separated by a Sylgard cork, through which the 
antennule passes. 
Neurophysiology 
Electrophysiological data were obtained from chemoreceptors of oil-exposed 
and normal lobsters, some of which had been observed behaviorally. This 
permits a comparison between the neural chemosensory input the animal 
received, and the resultant behavior after processing through higher nerve 
centers. Such a comparison is a necessary step in determining whether oil 
interferes with behavior through chemoreception. 
To measure neurophysiological activity, the lateral flagellum of the 
antennule of a lobster was removed and placed in fresh seawater. The cut 
proximal end was inserted through a Sylgard cork. Three to four cuticular rings 
were removed. The distal tip was cut and the antennule placed in a lobster 
saline bath in the stimulation-recording chamber (Figure 10-2). A micropipette 
was inserted snugly into the distal tip, and perfusion with oxygenated lobster 
