Power of Stinging.—The name Acalephce, Sea-Nettles, suggests thin property. It is not, however, improbable that this function is possessed only by a few species. Some possess this property in a remarkable degree, as the Cyanea capillata, which is a terror to bathers in our seas. At most two or three others possess it in relation to the human skin. It is probable they exert greater power over their prey or their enemies amongst the lower classes. The stinging power is supposed to reside in small capsular hairs, which are found in the tissues of the Acalephte as well as in Actinice and other polypes.
Phosphorescence.—On whatever property this phenomenon depends, there is no doubt that it is possessed in a high degree by almost every species of Medusce. The circumstances, however, on which it depends seem to be little known. On some occasions the A calephte with other marine creatures will give out abundance of light, whilst at other times not a glimmer can be observed.
The A calephe have been divided into four families : the Pulmograda, the Ciliograda, the Cirrhigrada, and the Physograda. The following is the arrangement of the Pulmograda given by M. de Blairsville, who, by intercalating the genera of P4ron and Lesueur, and of Esehscholtz, the existence of which he is far from guaranteeing, gives ua the follow ing synoptic table :— Eudora.
Generic Charader.—FG•ly very much depressed, discoid, simple, without tentneular cirrhi, without either peduncles or appendages, and offering within only ramified canals opening (nabouelumt) by four large trunks, in the form of a crow, into a small central cavity without external apertures Example, Eativro andukso (Nron and Lestneur).
there wall a membrane on the lower surfikee, and he inquires whether this was not perhaps some remains of the stumachal cavity.
envier united this genus with the Grryonia. Eachschults places it in his faultily Berrosiciihr, and unites Erryak with it Genrree C7.arartrr. Body hemispherical, sub-conical, or even semi elliptical, furnished on its circumference with foliaceous subtentacular lobos, hollowed below by a grunt atontachal excavation with an aperture as large as itself.
Example, CltaryLthro periphylla (1'6r. and Lea.).
.Equorea.
Generir Character. — Body slightly divensiform, furnished at i circumference with a circle of filamentous tentacular eirrhi, often very long, and more or less numerous, a good deal excavated below, with a median orifice often at the extremity of a sort of circular which is more or leas projecting or provided with tentacular fringes.
Stomachsl appendages linear, numerous, or saecifonn and not ,a, view of the upper side ; b, in profile, or with the edge of Its 'BA towards the spectator ; e, view of the lower side.
M. tie Yfinineille remarks that be only known this genus from the characteristic and short description given by Wron and Lesneur. lie doubts whether this 3jedteet has not a mouth ; for ho thinks that the centre of the reunion of the four large trunks of the canals ought to M. du Itlikinville divides this genus into the following section, — • Marginid cirrhi very numerous; ntonmehal appendages equally numerous and linear.
A. Lip pimple.
Coma .liquors.
11 Lill fringed.
Cenua Marcmona, (Each.) • • Marginal cirrhi as well as the stomachal appendages sufficiently numerous, or not numerous.
C. timid sufficiently numerous, originating opposite to the trian gular atomachal appendages.
Genus Poly.rena. (Each.) 1 D. Cirrhi and sacciform ntomachal appendages few.
Celina ..Egina. (Each.) We have selected a genus of the first subdivision for illustration.
be regarded as a stomach. Ile further inquires whether the individual figured was complete. lie says that M. Lemmur informed hit, that Menmantkns.
Generic Charartrr—Tiody hemispherical, provided at its circum ference with tentaculiform cirrhi which are bulbous at the root ; very much excavated beneath, and having In its middle a free 1es.aiicu)foim stomachal cavity dividing itself into clavifonm canals, and tenminutted, by a Himple buccal orifice.
Favonia.
Generic Chararter.—Body subhemispherical, with neither cirrhi nor tentaculiform marginal cilia ; rather deeply excavated beneath, with a long, median, proboscidiform prolongation, having at its root six or eight brachideous appendages, furnished with radiciform suckers. Four ovaries.
Example, Faronia Octoneme. (Orithyie Oetonema, Lam.) Hebitat.—South Seas.
Placed by P6ron among his Oceania.. Ilabitet.—Coasin of Europe; Holland.
Time.
Generic Character.—Body hemispherical, depressed, furnished on its circumference with a circle of tentaculiform cirrhi, which are short and numerous ; not much excavated beneath, and prolonged into a very thick conic peduncle, which is entirely exserted, and terminated • by a plicated enlargement ; buccal orifice at the centre of four labial appendages ; stomacbal cavity in the enlargement of the peduncle, and giving origin to four ascending canals, and communicating with a marginal canal.