The mechanic cause is the presence of air between the lamellae of the affected parts, but their origin is unknown.
"Anomalies and Curiosities of Medicine" by George M. Gould
At their bases there is a short subsidiary row of obliquely transverse lamellae.
"On the Origin of Species" by Charles Darwin
Very good specimens of Protuberans lamella.
"Scientific American Supplement, No. 384, May 12, 1883" by Various
One or two red Gemiasmas, starch, Protuberans lamella, Pollen.
"Scientific American Supplement, No. 385, May 19, 1883" by Various
In figure 4a are well seen the beautifully pectinated lamellae of the antennae in this genus.
"Discoveries in Australia, Volume 1." by J Lort Stokes
The gills or lamellae are the radiating parts, like knife blades, that extend from the centre to the margin underneath the cap.
"Among the Mushrooms" by Ellen M. Dallas and Caroline A. Burgin
Lamella: a thin plate or leaf-like process.
"Explanation of Terms Used in Entomology" by John. B. Smith
Lamella (lamellae), gills of a mushroom.
"The Mushroom, Edible and Otherwise" by M. E. Hard
The larger specimen had almost mature ova in the lamellae.
"A Monograph on the Sub-class Cirripedia (Volume 1 of 2)" by Charles Darwin
On either side of the body between the mantle and the foot are two flat gills each composed of two lamellae.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 6" by Various
Then, a lamella measuring 3 µm × 2 µm × 0.3 µm is cut out from this area of the wafer.
Measurement of statistical nuclear spin polarization in a nanoscale GaAs sample
The membranes are called lamellae in this context, and this phase is called the lamel lar phase.
From the symmetry point of view it is a (lyotropic) smectic A phase, and it is characterized by quasi-long range order in the positions of the lamellae, and long-range order in their orientations.
The lamellae lie on parallel planes, on average, in different regions of the sample.
On the other hand one may have an edge dislocation, where one lamella bends on itself, as in ﬁg. 32, or a more complicated screw dislocation, but with a mismatch of two in lamella number.