_P. compressa._ The compressed or flat-sided Patella. Pl. 2, fig. 2.
Oval, elongated, compressed on the sides, having the summit sub-anterior, well marked, and curved; exterior fawn colour, interior of a silvery hue.
_P. deaurata._ The golden red Patella. Pl. 2, fig. 3.
Sub-conic, summit more anterior, with a slight forward inclination; colour yellowish red.
_P. cochlear._ The spoonlike Patella. Pl. 2, fig. 4.
Depressed, the summit hardly marked, and much more narrow in front than behind; exterior brownish, interior light blue.
_P. scutellaris._ The buckler Patella. Pl. 2, fig. 5.
Depressed, summit sub-anterior, radiated from the summit to the margin; brown colour, with a yellowish band parallel to the margin.
_P. pectinata._ The pectinated Patella. Pl. 2, fig. 6.
Oval, summit well marked and anteriorly inclined; ribbed from the summit to the margin, which is slightly convex in the middle.
_P. cymbularia._ The cymbular Patella. Pl. 2, fig. 7.
Oval, thin, pearly, with a festooned margin; summit nearly marginal; colour white, shaded with very light brown.
The genera that constitute this family were separated by Lamarck from the Patella of Linnæus.
1. Parmaphora. The Duck’s-bill Limpet. Three species.
The characteristic distinctions of this shell were first pointed out by De Blainville.
Shell elongated, very depressed; the summit greatly post-medial, and evidently inclined behind; aperture as large as the shell; the lateral edges straight and parallel, the posterior rounded, the anterior sharp and notched in the middle; muscular impression large, elongated oval, slightly open in front.
Parmophora Australis. P. brevicula. P. granulata.
_P. Australis._ The Australian Parmophorus.
Shell oblong, depressed; vertex slightly recurved; striated concentrically; one margin rounded, and the other truncated.
2. Emarginula. The Slit Limpet. Four species.
Most of the shells of this genus are small; some are elevated, and others of a widely-depressed conical form.
Shell conical, recurved; summit entire; slit, or more or less hollowed on the anterior side; a muscular impression in form of a horseshoe, open behind and thicker at the beginning.
Emarginula Blainvillii. E. marginata. E. fissura. E. rubra.
_E. Blainvillii._ Blainville’s Emarginula.