The fibrillae, then, are bound together in a bundle to form a fiber, which is enveloped in its own sheath, the sarcolemma.
"A Practical Physiology" by Albert F. Blaisdell
Separated fibrillae highly magnified.
"The People's Common Sense Medical Adviser in Plain English" by R. V. Pierce
Fibrilla: rod or sliver-like nerve elements, often grouped like a bundle of short threads.
"Explanation of Terms Used in Entomology" by John. B. Smith
Sweeping fibrillae came down to the ground and seemed to serve as feet.
"Jimsy and the Monsters" by Walt Sheldon
While they consist of a "dual" thread, each unit of these is complex, being made up of a number of fibrillae.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 3" by Various
The elastic fibres were dissolved, broken up into fibrillae and these seemed to be absorbed.
"Arteriosclerosis and Hypertension:" by Louis Marshall Warfield