To put the case as I have before done, if a specimen of one of these parasites had been brought to me to class without any information of its habits,—the downward direction of growth in all the valves, the presence of a rostrum, the villose outer integument, all the details of the prehensile antennæ, the form of the animal’s body, and the position of the labrum, would have convinced me that, though a quite new genus, it ought to have stood close to Scalpellum, and nearer to it than to Ibla.

6. Scalpellum villosum. [Pl. VI], [fig. 8.]

Pollicipes villosus on Plate (TOMENTOSUS in text). Leach. Encyclop. Brit., Suppl., vol. iii, 1824, Pl. lvii.

————— villosus.[59] G. B. Sowerby. Genera of Shells, Pollicipes, fig. 3, 1826.

Calantica Homii. J. E. Gray. Annals of Phil., vol. x, p. 100, 1825.

[59] As Mr. Sowerby has adopted the name villosus, I have followed him; though as tomentosus is used through some mistake by Leach in the text, both names have equal claims as far as priority is concerned.

In Lamarck, ‘Animaux Sans. Vert.,’ the P. villosus of Sowerby is made synonymous with Anatifa villosa of Brugière, which is certainly incorrect, although the A. villosa of this latter author is not positively known.

S. (Herm.) valvis 14: sub-rostro præsente: carinâ pæne rectâ: laterum paribus tribus; pari superiore triangulo.

(Herm.) Capitulum with 14 valves: sub-rostrum present: carina nearly straight: three pair of latera; upper latera triangular.

Mandibles with four teeth, of which the second is the smallest: maxillæ with a projection near the inferior angle: no caudal appendage.