The powerful retractile talons of the falcon and cat tribes have not been produced or increased by the volition of those animals; .
"Luck or Cunning?"
Samuel Butler
All these structures are retractile, the retraction going on very slowly for a long time, as if the force of cohesion continued to act in the web of the structure even after its formation was complete.
"The Mechanism of Life"
Stéphane Leduc
A short distance behind the head were two tremendous reddish-brown fins, with strong supporting spines that seemed to terminate in retractile claws.
"The Terror from the Depths"
Sewell Peaslee Wright