Is the Frequency Content of the Calls in North American Treefrogs Limited by Their Larynges?

Figure 2

Experimental setup for laryngeal activation of frogs (mic. = microphone, amp. = amplifier, and cond. = condenser). Moist air is passed through the lungs of a euthanized frog and activates the larynx to produce sound. Pulmonary air pressure, airflow, and sound are recorded.