The Echinococcus Multilocularis is the variety in which there are a great many small cysts surrounded by dense connective tissue. These cysts contain pigment and calcareous matter, but seldom scolices; are usually sterile.

These various forms of echinococcus cysts are filled with a clear fluid of about 1009 to 1015 specific gravity; is neutral or alkaline, contains no albumin, but sodium chlorid is present and sometimes sugar.

A cyst may become very large or the fluid disappear by absorption and inspissation.

It may be harmless or dangerous according to its location. May undergo suppuration.

Is usually found in the liver, but may occur in lungs, kidneys, spleen, omentum, and in the brain.