Very little is known concerning the life-history and development of the Stauromedusae. FAM. 1. LUCERNARIIDAE.—Marginal lobes digitate, bearing the capitate tentacles in groups. _Haliclystus auricula_ is a common form on the shores of the Channel Islands, at Plymouth, and other localities on the British coast. It may be recognised by the prominent statorhabs situated in the bays between the digitate lobes of the margin of the umbrella. Each of the marginal lobes bears from 15 to 20 capitate tentacles. It is from 2 to 3 cm. in length. The genus occurs in shallow water {321}off the coasts of Europe and North America, extending south into the Antarctic region. _Lucernaria_ differs from _Haliclystus_ in the absence of statorhabs. It has the same habit as _Haliclystus_, and is often found associated with it. _L. campanulata_ is British. _Halicyathus_ is similar in external features to _Haliclystus_, but differs from it in certain important characters of the coelenteric cavities. It is found off the coasts of Norway, Greenland, and the Atlantic side of North America. In _Capria_, from the Mediterranean, the tentacles are replaced by a denticulated membrane bearing nematocysts. The rare genus _Tessera_, from the Antarctic Ocean, differs from all the other Stauromedusae in having no stalk and in having only a few relatively long non-capitate tentacles. If _Tessera_ is really an adult form it should be placed in a separate family, but, notwithstanding the presence of gonads, it may prove to be but a free-swimming stage in the history of a normally stalked genus. FAM. 2. DEPASTRIDAE.—The margin of the umbrella is provided with eight shallow lobes bearing one or more rows of tentacles. Statorhabs absent. _Depastrum cyathiforme_ occurs in shallow water at Plymouth, Port Erin, and in other localities on the coasts of Britain and Norway. The tentacles are arranged in several rows on the margin of the umbrella. In _Depastrella_ from the Canaries there is only one row of marginal tentacles. FAM. 3. STENOSCYPHIDAE.[356]—Stauromedusae with simple undivided umbrella margin. The eight principal tentacles are converted into adhesive anchors. Secondary tentacles arranged in eight adradial groups. _Stenoscyphus inabai_, 25 cm., Japan. ORDER III. CORONATA.[357]