Alternate header for print version

Public Domain: This image is in the public domain and thus free of any copyright restrictions. However, as is the norm in scientific publishing and as a matter of courtesy, any user should credit the content provider for any public or private use of this image whenever possible. Learn more
*CIL – Cell Image Library accession number. Please use this to reference an image.

CIL:36778*  Cite 

The three ciliary membranelles in the buccal cavity from which this class of ciliates gets its name, Oligohymenophorea, are each composed of four rows of basal body/cilium complexes. The quadrulus has four rows of cilia less tightly packed and interspersed with parasomal sacs. The dorsal and ventral peniculi are more tightly packed. In this micrograph only 6 or 7 rows of peniculi are present at this level since the rows of the peniculi do not go all the way to the posterior end but rows end in a staggered way somewhere along the length of the buccal cavity. The quadrulus borders the cytopharynx over its full length and goes to the posterior end of the buccal cavity. TEM taken on 3/30/73 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 10,750X. Bar = 0.5µm.

Technical Details

Standard glutaraldehyde fixation followed by osmium tetroxide, dehydrated in alcohol and embedded in an epoxy resin. Microtome sections prepared at approximately 75nm thickness. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. There is a high resolution version of this image in the library (CIL:39162) which is available for quantitative analysis. Additional information available at (

Biological Sources
NCBI Organism Classification
Paramecium caudatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
oral apparatus
Biological Context
Biological Process
oral apparatus organization
Richard Allen (University of Hawaii)
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Grouping This image is part of a group.
Image Type
transmission electron microscopy (TEM)
illumination by electrons
Image Mode
detection of electrons
Parameters Imaged
electron density
Source of Contrast
stain with broad specificity
Visualization Methods
stain with broad specificity
uranyl salt
lead salt
osmium tetroxide
Processing History
recorded image
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Spatial Axis Image Size Pixel Size
X 3076px ——
Y 3456px ——