Long. tot. 5 unc.; _rostri_, ¾; _alæ_, 2⅝; _caudæ_, 1¾; _tarsi_, ¾. Fœm. _Corpore superiore, gutture pectoreque intensè brunneis, singulis plumis pallidiorè marginatis; abdomine crissoque cinereis, stramineo tinctis; rostro pallidè fusco; pedibus nigrescenti-fuscis._ Deep sooty black, with the under tail-coverts white; the bill and feet blackish brown. Female: Upper surface of the body, throat and breast intensely brown, with the margins of each feather paler; the abdomen and the under tail coverts cinereous, tinged with straw colour; the bill pale fuscous, and the feet blackish fuscous. Habitat, Galapagos Archipelago, (James’ Island.) [Illustration: _Birds. Pl. 42._ _Cactornis scandens._ ] [Illustration: _Birds. Pl. 43._ _Cactornis assimilis._ ] The species of this sub-genus alone can be distinguished in habits from the several foregoing ones belonging to Geospiza and Camarhynchus. Their most frequent resort is the _Opuntia Galapageia_, about the fleshy leaves of which they hop and climb, even with their back downwards, whilst feeding with their sharp beaks, both on the fruit and flowers. Often, however, they alight on the ground, and mingled with the flock of the above mentioned species, they search for seeds in the parched volcanic soil. The extreme scarceness of the jet black specimens, which I mentioned under the head of the genus _Geospiza_, is well exemplified in the case of the _C. scandens_, for although I daily saw many brown coloured ones, (and two collectors were looking out for them), only one, besides that which is figured, was procured, and I did not see a second. 2. CACTORNIS ASSIMILIS. _Gould._ PLATE XLIII. TISSERIN DES GALLAPAGOS, (île St. Charles,) _Neboux_, Revue Zoologique, 1840, p. 291. _C._ Mas (jun?) _corpore suprà fuliginoso, (gutture abdomineque exceptis,) cinereo marginatis; rostro pallidè rufescenti-brunneo; pedibus nigrescenti-brunneis._ Long. tot. 5½ unc.; _rostri_, ¾; _alæ_, 2¾; _caudæ_, 1¾; _tarsi_, ¾. Upper surface of the body sooty black, margined with cinereous, as well as the throat and abdomen; the bill pale rufous brown; the feet blackish brown. Habitat, Galapagos Archipelago. I do not know from which island of the group this species was procured; almost certainly not from James Island. Analogy would in this case, as in that of _Camarhynchus crassirostris_, lead to the belief that the old male would be jet black. By a mistake this bird has been figured standing on the _Opuntia Darwinii_, a plant from Patagonia, instead of the _O. Galapageia_. I may here mention that a third and well characterized species of Cactornis has lately been sent by Captain Belcher, R.N. to the Zoological Society; as Capt. Belcher visited Cocos Island, which is the nearest land to the Galapagos Archipelago, being less than 400 miles distant, it is very probable that the species came thence.