Zoological Illustrations/VolII-Pl118

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Zoological Illustrations Volume II Plate 118.jpg

CONUS Generalis,

Flambeau Cone.

Generic Character.—See Pl. 65.

Specific Character.

C. testâ gracili, fuscâ, fasciis albidis strigis undatis longitudinalibus interruptis ornatâ; spiræ productæ apice acuto, anfractibus concavis, lævibus; basi nigrâ.
Shell slender, brown, with white bands, interrupted by longitudinal stripes; spire produced, the tip acute, whorls concave, smooth; base black.
Conus Generalis. Gmelin, p. 33. 75. var. a. Dillwyn, 359. var. a. Martini, vol. 2. p. 58. f. 645, 646. (dark variety) f. 648 to 652. (pale varieties). Gualt. 20 f. G.
Conus Generalis. Brug. p. 642. Lam. Ann. vol. 15. p. 363.

It becomes necessary to figure this elegant, but not uncommon Cone, in order to show the young conchologist the little importance that should be attached to colour in the discrimination of species: the figures will likewise point out more fully the distinctions between the present shell, C. maldivus, and C. cinctus; three species, whose close affinity require illustration.

These relative distinctions may be comprised in a few words; they rest principally on the spire, which in C. generalis has the upper half much lengthened, slender, and acuminated: in C. maldivus the spire is thick and much shorter: the whorls in both these species are quite plain, and nearly flat: the spire of C. cinctus resembles the last in form, but is deeply concave and striated. These characters are, I think, very satisfactory as specific distinctions.

On the other hand, some attention to these shells lately, has convinced me that many of the species formed both by Bruguiere and Lamarck should be more correctly considered as varieties; inasmuch as their specific distinctions rest, for the most part, on colour alone: this appears, indeed, to be the leading character selected by these eminent conchologists, and to which, therefore, they have attached the greatest importance. From this opinion, however, I completely dissent; on the principle, that no character which is variable can, with any consistency, be made use of to express permanent distinctions, when not supported by peculiarity of formation or sculpture. The great art in framing the description of a species consists in singling out those characters alone which are most permanent, and exist in every variety of that species; for, when once a character is found to be variable, it no longer becomes a distinction by which a species can be recognised. I consider, therefore, formation and sculpture as the only certain characters of species, and that variation of colour should alone distinguish varieties.

It is therefore not surprising that the specific characters given by MM. Bruguiere and Lamarck, and resting principally on the colours of these shells, are frequently obscure, and always long; two inevitable evils attending every attempt to describe minutely the colour, form, and disposition of the markings of shells. In justice, however, to these great naturalists, it should be observed, that in this attempt they have done that best which no writer has ever done well.

The spire of C. generalis is generally spotted, and the white band on the margin of the body whorl, more or less crossed by broad waved stripes of a dark brown. It is an inhabitant of many parts of the Indian Ocean.