when this is removed, the surface is shining and pearly, of an emerald-green color, lighter on the keels. It is one of our most curious shells. VALVATA PUPOIDEA.—(Gould.) Shell small, elongated-ovate, opaque, chestnut-colored, when divested of the rough, dirty pigment which usually adheres closely to it; whorls four or five, minutely wrinkled, the posterior one small and flattened so as to form an obtuse apex; the others cylindrical, and so partially in contact as to expose about one half of the cylinder; the last entirely disjoined from the preceding one for at least the half of a revolution ; aperture circular, lip simple and sharp; on looking at the shell from below, no umbilical opening is found; operculum horny, apex central, elements concentric. Length inch, breadth 1⁄2 inch. Found at Fresh Pond and other ponds, on stones and submerged sticks; and has been for many years in our cabinets marked as a PALUDI'NA. Animal very active; head proboscidiform, half as long as the tentacles, bi-lobed in front, dark, terminated with light; tentacles rather stout, light drab-colored, with a line of silvery dots on the upper side, over the large, black eyes; foot, tongue-shaped, as long as the first whorl, dilated into two acute angles in front, light drab-color; respiratory organ occasionally protruded to half the length of a tentacle on the right side. This species is widely distinguished from all other described ones by its minuteness, its elongated form, and its want of an umbilicus; of which characters the last two seem to arise from the loose manner in which the whorls are united. AMNICOLA PORATA.-(Say.) Shell minute, conic-globose, thin, translucent, smooth, or with most delicate lines of growth; varying from a bronze-green to a light olive-green color, but usually invested with mud; whorls four or less, very convex, and flattened near the suture, so as to present a conspicuous shoulder; the last whorl rather more than two thirds the length of the shell, and as broad as long; suture deeply impressed, almost channelled; aperture nearly circular, both lips being about equally curved, and uniting posteriorly at a broad angle; lips sharp, in some instances a little everted; inner lip, at maturity, barely touching the preceding whorl just before it joins the outer lip, leaving a very large, deep umbilicus. Length inch, divergence 68°. inch, breadth Found in ditches and brooks, clinging to stones or submerged plants, oftentimes iu great numbers. Animal a light drab color tinted pink, the head a little fleshcolored above; tentacula silvery, with a dark line running along the outside from the eyes, which are at the external base; foot not reaching beyond the first whorl, broadly rounded behind, dilated into angles at each side in front; head half the width of the foot, and projecting beyond it, motions very slow. In delicate and clean specimens, a dark mark parallel to the outer lip, and another bisecting it, and belonging to the animal, appear through the shell. Under this species I include all the small shells, hitherto regarded as PALUDI'NE, which are collected in this region, ascribing the very great differences they present in color and size to differences of locality and age. The shoulder of the whorls, the conspicuous umbilicus, and the rounded aperture, almost like VABVA'TA or CYCLOSTOMA, are the most obvious characters. It is less solid, less elongated, the aperture more circular, and the inner lip much less closely appressed to the preceding whorl than P. limosa Says P. lustrica, Say, is described as much smaller, much more elongated, and more cylindrical. This I strongly suspect to be identical with valvata pupoidea in an immature state. It approaches nearest to P. Cincinnatiénsis, Anthony, which is larger and more conical and elongated. ARTICLE XXIII.-On the Order Lepidoptera, with the description of two species of Canadian Butterflies. On reference to the classification of the Animal Kingdom, published in the first number of this magazine, Feb. 1856, p. 26-31, it will be seen that the second Department or Division Articulata is divided into three classes: Insecta, Crustacea, and Annelides (or worms). The first of these three classes is further divided into three sub-classes, viz.: Manducata (or Mandibulata,) insects with jaws; Suctoria (or Haustellata,) insects with a sucker; and Aptera, or wingless insects. The second of these sub-classes con tains several orders, viz.: Lepidoptera, or Butterflies and Moths; Diptera, or two-winged flies; and Hemiptera, bugs, boat-flies, &c. The present article deals with the first of these orders. In future numbers we shall probably give a sketch, not only of the remaining orders of Suctoria, but also of Mandibulata and Aptera. INSECTA HAUSTELLATA.-ORDER LEPIDOPTERA. Butterflies and Moths are distinguished from all other insects, by having the wings clothed with scales. The scientific term "Lepidoptera" is derived from two Greek words, lepis, a scale, and pteron, a wing. Their wings are not transparent like those of a bee, a fly, or a dragon-fly, nor are they horny like the elytra of a beetle, but both surfaces are thickly covered with small scales, which are easily removed, and laid one over the other with great regularity like tiles on the roof of a house. If these be rabbed off, the membrane of the wing is left entirely colourless. It is to these scales, therefore, that they owe the splendid colours which render them the objects of such universal admiration. The order is divided into two great Sections: 1. Rhopalocera, containing the Butterflies, and of which we shall presently treat; and 2. Heterocera, which includes the Hawkmoths, Bombyces, Noctuæ, Geometræ, &c.; or, in short, all the Lepidoptera not having a knob to the antennæ. They all alike pass through the stages of egg, larva, pupa, and imago; and the larva, or Caterpillar, changes its skin several times before it becomes full fed, when it changes to the Pupa, without legs and motionless, frequently forming for its protection in that state, a cocoon of silk, which, in some species, has been an article of commerce from the earliest ages. Want of space compels us to conclude this brief and imperfect sketch of this interesting order, which is supposed to contain more species than any other except Coleoptera; and we now proceed to the consideration of the SECTION 1.-RHOPALOCERA, Boisduval. LEPIDOPTERA DIURNA, Latrielle. (BUTTERFLIES.) The Diurnal Lepidoptera, or Butterflies, corresponding with the Linnean genus Papilio, are distinguished from all other Lepidoptera, by having the antennæ long and slender, and terminated by a knob, or club. In the Hesperidæ this club is hooked at the * Certain foreign genera, however, such as Morpho and Urania, form an exception to this rule, as they have antennæ either of equal thickness throughout or tapering slightly at the summit. |