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Re: Gastralia question



> I read somewhere (ok, in a copy of Romer's "The Vertebrate Body") that 
> gastralia are of dermal origin. Does this mean gastralia, as well as 
> scutes and similar dermal thingies appear all of a sudden -without going 
> first through the cartilage phase- in the embryonic stages 
 
Yes. Like most skull bones that are visible from outside, and like the 
clavicles. (Though it isn't always that easy. Clavicles are "secondarily 
endochondral", which means, IIRC, that while they ossify cartilage appears 
and then ossifies, too. This may be behind the BAND idea that the furcula 
could include the interclavicle... ignoring the fact that the 
interclavicle is dermal, too.) 
 
> I apologize if the question is dumb., ok? 
 
No. Never. Jump out of the window. C'mon, c'mon... 

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