Expanse of wings 1 inch 4 1/2 lines.

Hab.  Australia.

Eurybrachys LAETA, pl. 4, fig. 3.

Head thorax and upper wings of a rich brown colour, the outer edge of the last is deep black, with a transverse yellowish spot just before the middle, the remainder of the edge slightly spotted with black, upper side covered with short blackish hairs; lower wings deep black; abdomen of a bright red, with a round white tuft on the upper side near the end; first two pairs of legs of a deep brown, with some reddish lines; hind legs ferruginous with blackish spines.

Expanse of wings 7 lines.

Hab.  Australia.

Tettigarcta, n. genus, white.  Fam.  CICADIDAE.

Head very small in front, blunt; lateral ocelli close to the eyes, space between them with long hairs.

Prothorax very large, extending back in a rounded form beyond the base of hind wings, the sides sharp pointed, the back very convex and wrinkled.

Body and under parts densely clothed with hair.

This very singular genus differs from all the Stridulantes in the size and shape of the prothorax; in the neuration of the elytra it is allied to PLATYPLEURA (Amyst and Serville) in the size of head and hairiness of body it approaches CARINETA of the same authors.  The Pupa, (fig. 5.) differs in the form of fore legs from those of the other Cicada.

Tettigarcta TOMENTOSA, pl. 4, fig. 4, and 5 its pupa.

Of a brownish ash colour, the hairs on upper part of body short and deep brown, on the sides and under parts long and grey; prothorax varied with black, in front, two large patches covered with grey hairs, mixed with longer; elytra spotted and varied with brown, wings clear, somewhat ferruginous at the base.

Expanse of wings 3 inches 4 lines.

Hab.  Australia.

* * * * *

DESCRIPTION OF TWO NEW INVERTEBRATED ANIMALS FROM AUSTRALIA, BY J. E. GRAY, ESQ., F.R.S.

Lamarck separated the mother-of-pearls shell (Margarita) from the swallow-tail muscles (AVICULA) on account of its more orbicular shape.  Other Conchologists have been inclined to unite them, as some of the species of AVICULA approach to the shape of the other genus.  The new one just received from Australia, which I am now about to describe, in this respect more resembles the Margarita than any before noticed; yet I am inclined to think that the pearl-shells deserved to be kept separate, as the cardinal teeth are quite obliterated in the adult shells, which is not the case with any AVICULAE I am acquainted with; and the young pearl-shells are furnished with a broad serrated distant leafy fringe, while the AVICULAE are only covered with very closely applied short concentric slightly raised minutely denticulated lamina, forming an epidermal coat on the surface.

1.  AVICULA LATA, pl. 6. f. 1.