canal is more restrictive and does not allow for the increase of space for more neurons and also does not allow the clustering of ganglion axons which makes this structure more restrictive when concerning the variation of ganglion. The highly derived spiral ganglion structure of the inner ear in Yangochiroptera, the suborder of Coleura seychellensis, is referred to as a trans-otic ganglion with a wall-less Rosenthal canal and is what makes echolocation work so well in bats of a similar evolutionary pathway. Vocalization Within echolocation, there is vocalization which can be best described as how a frequency is altered for different purposes and needs. At a family level (Emballonuridae) four call structures have been described, broadband FM (Frequency modulation), narrowband FM, long multi-harmonic calls and short multi-harmonic calls. Broadband FM is simply an FM sweep, narrowband FM is a downwards FM sweep that is then followed by a more narrow band tail. Long multi-harmonic calls are calls that have a minimum of 4 narrowband FM harmonics in a 2 ms period. Similarly, short multi-harmonic calls are ones that also have 4 narrowband FM harmonics but in under 2 ms. The structure of calls can be altered for a specific need, they can be faster, slower, louder, or quieter from a source individual depending if they are hunting, navigating, communicating, protecting territory, or courting a mate. To date, there are 21 simple syllables and 62 composite syllables in Saccopteryx bilineata males which are in the same family, Emballonuridae, as Coleura seychellensis. Using these syllables there are seven vocalization types in the species S. bilineata, identified as pulses, barks, chatter, whistles, screeches, territorial songs, and courtship songs. Pulses have a CF (constant frequency), start with an upward FM hook, end with a downward FM hook, and last about 7.4 ms. Barks are similar to pulses but are longer at about 10.5 ms and mainly come from males. Chatter calls are in sequences of up to 50 calls in about 5.5 ms, a single chatter call can resemble pulses but usually has a higher degree of FM. Whistles are very loud and tonal vocalizations by males hovering in front of females and last about 66.7 ms, start with a FM upstroke, increasing in fundamental frequency, and end with a FM downstroke. At the same time females vocalize a screech that can last up to 300 ms and are related to territorial conflicts and