Typus Genericus _Nerita Glaucina_ Pennant.
Sh.e.l.l nearly globose, or oval, umbilicated. Spire depressed, very small. Columella terminating in the middle of the umbilicus. Aperture semi-circular, operculum either h.o.r.n.y or testaceous. Animal marine, with a large foot; the eyes placed at the base of two simple tentacula.
Generic Type _Nerita Glaucina_ Pennant, &c.
SPECIFIC CHARACTER.
_N. testa sub-globosa, fusca, albo fulvoque fasciata, juxta suturam striata; labio exteriore supra leviter emarginato; umbilico magno, aperto; columella obsolete terminante._
Sh.e.l.l sub-globose, striated near the suture, brown, banded with white and fulvous; outer lip above slightly emarginate; umbilicus large, open; pillar termination nearly obsolete.
_Martini_ 5. _pl._ 187. _fig._ 1872 _&_ 3. _fig._ 1874 & 5? _pl._ 188.
_fig._ 1896, 8 _&_ 9.
_Seba_, _pl._ 38. _fig._ 66. _pl._ 41. _fig._ 14, 15.
The Sh.e.l.ls of this genus are composed of such of the Linnaean _Nerits_ as are umbilicated, from which latter they essentially differ, both in the organization of the animal and the construction of the sh.e.l.l, which is either closed by a sh.e.l.ly or h.o.r.n.y operculum.
The species are numerous, and are found both in temperate and tropical seas; two or three inhabit our own coasts, but by far the greater number are found in the Asiatic Ocean. They are subject to variation in their colour; and this, joined with a general resemblance in form, has rendered the discrimination of the species very difficult. I have, however, remarked, that the various modifications of the umbilicus, and the termination of the pillar (which is indicated in many species by an elevated ridge or rib within the umbilicus) is a certain and constant indication, presenting the same peculiarity through all the individuals of a species, even in the young state. This termination of the pillar has been mistaken for the inner lip, which, on the contrary, is always above the umbilicus, which, if closed, is not closed by the lip, but by the thickened termination of the pillar or columella.
The two most striking varieties are here figured of this species, which is sufficiently described in the specific character. I believe it is found both in the Mediterranean and Red Seas.
Pl. 76
[Ill.u.s.tration]
MEROPS Savignii,
_Black-capped Bee-eater._
GENERIC CHARACTER.--See Pl. 8.
SPECIFIC CHARACTER.
_M. viridis, subtus albescens, uropygio caudaque caeruleis; vertice, striga oculari, fasciaque lata collari nigris; mento, superciliisque albis; rectricibus mediis elongatis._
Green; beneath whitish; rump and tail blue; crown of the head, eye stripe, and broad band across the neck, black; chin and eye-brows white; two middle tail feathers lengthened.
This Bird was pointed out to me by Professor Temminck as described by Le Vaillant in his work on this family, under the name here given; on this authority, therefore, I have been obliged to rest, for I have in vain turned over the catalogues of all the public libraries in the metropolis, in the hope of seeing the work, and ascertaining the fact. The book is modern, and, though expensive, one of standard excellence; but a princely fortune is necessary to purchase such a library as a student should have access to.
Total length eight inches and a half; size rather less than the common bee-eater; the crown in young birds is greenish, in some a dull brown, and in others deep black, margined in the front and sides of the head with a line of white; the ears black, uniting to a broad band across the neck of the same colour, which is margined on the lower part with beautiful sea blue; the nape of the neck, inner covers, and quill feathers, greenish fawn colour; the lesser quills tipt with black; the rump, tail, and outside of the quills next the body changeable greenish blue; the back and upper covers green beneath; the chin is white; the body tinged with greenish, and the under tail covers with blue: the tail three inches long, and in such specimens as have the two middle feathers lengthened, three and a half; bill and feet black.
Inhabits Sierra Leone, and other parts of Africa.
Pl. 77
[Ill.u.s.tration]
BOTIS,
_Gauze-wing._
GENERIC CHARACTER.
_Antennae setaceae. Alae trigonae, insecto sedente, c.u.m corpore triangulum subhorizontale efficientes, superiores margine externo recto. Palpi quatuor exserti. Lingua conspicua._ Latreille, _Gen. Ins._ 4. p. 229.
Typus Genericus _Ph. Urticata_ Lin. &c.
Antennae setaceous. Wings trigonal, forming a nearly horizontal angle with the body when the insect is at rest. The outer margin of the anterior wings straight. Palpi four, exserted. Tongue conspicuous.
Generic Type _Ph. Urticata_ Lin. &c.
Botys. _Latreille._
BOTIS marginata,
_Pink-margined Gauze-wing._
_B. alis hyalinis, stramineis, apicibus margineque flexuoso rubro-purpureis._
Wings hyaline; pale fulvous; the margins and tips with a waved reddish purple border.
P. Marginata. _Cramer_, _pl._ 400. I.--P. Simiata. _Fab. Ent. Sys._ 3.
208.