Umbrella
a light frame covered with silk, cotton, alpaca, or other fabric, and held above the head as a protection against sun or rain. The use of the umbrella came to us from the East, where it has been in use from remote times, and where it is considered as a symbol of royalty or dignity. As a defense against rain it was not generally used in the Occident till the middle of the 18th century.
In zoölogy, the bell-shaped swimming organ of the Lucernarida, akin to the nectocalyx of the Medusidæ, but without a velum. In zoölogy and palæontology, Chinese umbrella shell; a genus of Pleurobranchidæ, with six recent species, from the Canaries, Mediterranean, India, China, and the Sandwich Islands. Shell small, depressed, and limpet-like, marked by concentric lines of growth; inner surface with a central colored and striated disk, surrounded by a continuous irregular muscular impression. Animal with a very large foot, deeply notched in front, gill forming a series of plumes beneath the shell in front and on the right side.
Fossil species four, from the Oölite onward of the United States, Sicily, and Asia.