NATICA melastoma,
_Black-mouthed Natica--lower figures._
_N. testa depressa, fusca; spira complanata minima; ore intus atro-purpureo; umbilico magno, clauso labio interiore rufo._
Sh.e.l.l depressed, brown; spire flattened, very small; mouth within purplish black; umbilicus large, closed up by the inner lip, which is rufous.
In colour this bears a close resemblance to the last, but the sh.e.l.l is flattened beneath, and the spire very short and depressed; the umbilicus large, but, in general, quite closed up by the thickness of the pillar, united to the inner lip. In some specimens a narrow crescent-shaped groove is left on the outside margin. Its habitat is unknown.
Pl. 80
[Ill.u.s.tration]
HALIOTIS Californiensis,
_Small-holed Californian Ear-sh.e.l.l._
GENERIC CHARACTER.
_Testa univalvis, depressissima, lata, auriformis. Discus admodum perforatus. Spira minuta, depressa. Apertura testam magnitudine pene aequans, intus margaritifera._
Typus Genericus _H. Tuberculata_ Linn. &c.
Sh.e.l.l univalve, greatly depressed, broad, ear-shaped, the disk with many perforations. Spire minute, depressed. Aperture nearly as large as the sh.e.l.l; inside pearly.
Generic Type _H. Tuberculata_ Linn. &c.
SPECIFIC CHARACTER.
_H. Testa ovali, laevi, obscure thala.s.sina; labio exteriore supra immarginato, interiore lato, complanato, foraminibus numerosis, minutis, orbicularibus, laevibus._
Sh.e.l.l ovate, smooth, obscure sea green; outer lip above immarginate; inner lip broad, flat; perforations numerous, very small, orbicular and smooth.
The Ear-sh.e.l.ls are strangely characterized by their peculiarity of form, perforated holes, and rich pearly interior. They are found in both temperate and tropical seas; but the definitions. .h.i.therto given by conchologists are so imperfect, that they have left our knowledge of these sh.e.l.ls nearly the same now, as in the time of Linnaeus. Seventeen species only are enumerated in Mr. Dillwyn"s work; although thirty-four have fallen within my own observation the last few months.
The difference between this and the common black Californian Ear, consists in its being a much deeper and smoother sh.e.l.l, always narrowest at the base, the outer lip not having (as in that) a prominent curve or gibbosity where it joins the spire; but princ.i.p.ally in the perforations, which in this are always half as large, and doubly numerous; it is also generally a much smaller, and less common species: the spire is always deeply tinged with pink. The genus _Padollus_, of Montford, resting entirely in the unevenness of the outer lip, without any knowledge of the animal, appears to me an unnecessary distinction, for such is the character of all young sh.e.l.ls, and also of mature ones, whose outer surface is rugged or uneven.
Pl. 81
[Ill.u.s.tration]
SPHINX Ello.
GENERIC CHARACTER.
_Antennae prismaticae, in utroque s.e.xu ad medium leviter cra.s.sescentes, externe breviter piloso baciliatae, mucrone arcuato, producto, sensim terminantes. Palpi breves, obtusi. Lingua elongata, convoluta, distincta, et in pupa aliquando porrecta. Alae sub-integrae. Abdomen elongatum, conic.u.m, ano acuto, imberbi._
Typus Genericus _Sphinx Convolvuli_ Linn.
Antennae three sided, in both s.e.xes slightly thickened in the middle, externally ciliated with double tufts of short hairs, and ending in a gradually lengthened arcuated hook. Palpi short, obtuse. Tongue long, convolute, distinct, sometimes porrected in the pupa state. Wings nearly entire. Abdomen lengthened, conic; the tip pointed, and not bearded.
Generic Type _Sphinx Convolvuli_ Linn.
SPECIFIC CHARACTER.
_S. alis subdentatis, cinereis (in maribus lineis fuscis variatis); posticis rufis, margine nigro; abdomine pallido, cingulis atris circ.u.mdato._
Wings slightly dentated, cinereous (in the male variegated with brown lines); posterior rufous, with a black margin; abdomen pale, with black belts.
_Gmelin_ 5. 2375. 13. _Fab. Ent. Sys._ 3. 362. _no._ 21. S. Ello.
_Drury_, vol. i. p. 59. _pl._ 27. _fig._ 3. (_male._) _Cramer_, _pl._ 301. D.
It is in all things better to understand few subjects well than many imperfectly; knowledge may be extensive, but it cannot be sound, if it is at the same time imperfect; and, applying this observation to the present article, it becomes as desirable, where necessary, to ill.u.s.trate an insect known to Linnaeus, as to regard only the accession of new species.
The two insects figured were received from Jamaica by my friend Dr. Leach, and there can be no doubt they are the s.e.xes of one species. The upper is a male, and agrees with Drury"s figure and description; the lower insect is a female, of which no representation has been published: as for Cramer"s figure, if intended for the former, it is really so bad that it can hardly be quoted as an authority, and it appears to have misled Fabricius, in thinking that the female insect had a brown stripe on the anterior wings, whereas that character is more applicable to the male.
The insects I propose retaining under this genus are such as have the body lengthened, pointed, and not bearded at the tip; the antennae but slightly thickened in the middle, and the terminating hook gradual, arched, and not very acute: these comprehend the first section of Latreille"s genus, _Sphinx_, and are by him again divided into two groups, the one having the wings entire, the other angulated.
Pl. 82
[Ill.u.s.tration]
TROCHILUS niger,