I investigate the Baryonic Tully-Fisher relation for a sample of galaxies with extended 21 cm rotation curves spanning the range 20 \lesssim V _ { f } \leq 300 \mathrm { km } \mathrm { s } ^ { -1 } .
A variety of scalings of the stellar mass-to-light ratio \Upsilon _ { \star } are considered .
For each prescription for \Upsilon _ { \star } , I give fits of the form { \cal M } _ { d } = { \cal A } V _ { f } ^ { x } .
Presumably , the prescription that comes closest to the correct value will minimize the scatter in the relation .
The fit with minimum scatter has { \cal A } = 50 { \cal M } _ { \odot } \textrm { km } ^ { -4 } \textrm { s } ^ { 4 } and x = 4 .
This relation holds over five decades in mass .
Galaxy color , stellar fraction , and \Upsilon _ { \star } are correlated with each other and with { \cal M } _ { d } , in the sense that more massive galaxies tend to be more evolved .
There is a systematic dependence of the degree of maximality of disks on surface brightness .
High surface brightness galaxies typically have \Upsilon _ { \star } \sim \text@frac { 3 } { 4 } of the maximum disk value , while low surface brightness galaxies typically attain \sim \text@frac { 1 } { 4 } of this amount .