X-ray emission spectra have been recorded from several biologic tissues using a multichannel energy-dispersive analyzer with a retractible semiconductor detector coupled to a Cambridge Mark II scanning electron microscope. Particular attention has been given to the detection of silver in experimental argyria, of calcium in dermoid scales and in experimental necrosis of the kidney and of sulfur in the inner and outer portions of reptilian skin. Sulfur and chlorine have been found associated with silver in argyria. Phosphorus was associated with calcium both in the dermal scales and in necrotic areas. In addition to these elements, trace amounts of copper, zinc, lead, sodium, potassium, iron, arsenic, osmium and uranium have been detected in various normal and experimental situations. The applicability of the combined instrument to cytochemical problems is briefly discussed.

The basic structure of motile cilia is remarkably similar in different species and in various specialized epithelia. Few variants in the morphology of cilia have been recognized. Exceedingly long cilia have been termed flagella and considered as a separate type. In the retina, rods and cones are modified ciliary structures. The saccus vasculosus, a diverticulum of the cerebral third ventricle of fishes, contains crown or coronet cells, so called because of the bulbous tips of the short club shaped cilia. Figure 1 is a transmission electron micrograph of the saccus vasculosus and Figure 2 is a scanning electron micrograph of the crown cells viewed from above. Kinetocilia elsewhere have been thought to have almost identical morphology except for variations in the apical or basal terminations of the peripheral intraciliary fibers.

Antibodies produced to steroid hormone-protein conjugates have been tested for antihormonal properties. The passive administration of antibodies elicited by testosterone-3-bovine serum albumin (BSA), estrone-17-BSA, cortisol-21-BSA and aldosterone- 21-BSA to appropriate test animals has demonstrated that these antibodies can neutralize the biological effects ordinarily caused by the exogenous administration of the corresponding steroid hormone. (Endocrinology74: 593, 1964)

Testosterone, cortisone, deoxycorticosterone, estrone, and progesterone act as haptens when they are conjugated with bovine serum albumin. Antibodies with steroid specificity are formed in rabbits immunized with each of the five steroid hormone-protein conjugates.