_Bill_ entire, the sides much compressed, the culmen arched. The lower mandible recurved at the tip. _Wings_ very long. _Tail_ scansorial, the extremity of the shafts naked, and acute. _Tarsi_ naked, the three anterior toes and claws nearly equal; hind toe not versatile. _Nob._ Type. _Chætura pelasgia._ Stevens. ---- SPECIFIC CHARACTER. _Brown: wings and tail glossed with greenish blue; back grey-white: chin and under tail covers snowy; tail even._ Ob. Tail 3½ in. longer than the wings, the two first quills longest and equal. ---- For an inspection of this new and imposing species, we have to thank Mr. Ward, an Animal preserver of considerable talent. We do not find it mentioned in any Ornithological work we possess, and our library is not small: but with so many publications continually issuing from the continental press, we shall feel no surprise at discovering it has already been published. This and the _Hirundo albicollis_, (first named by M. Vieillot) are two of the largest species yet discovered, of a very singular group of Swifts; wherein the tail feathers are spined, and even more rigid than those of the Woodpeckers: by this structure the birds can remain for a considerable time in the most perpendicular situations. The expanded tail thus acts as a powerful support, which is further increased by the size and strength of the claws, much larger than those of ordinary Swallows. There are several species, most of which are natives of America. The direct analogy which this group bears to the typical scansorial Birds, joined to the general superiority of flight which the Swift possesses over the Swallow, leads us to suspect this may prove to be the typical group of the _Fissirostres_; an order in which Nature, in her wish to develope the greatest powers of flight, appears to neglect all those laws which she afterwards so rigidly adheres to: We intend in another work, to enter on this interesting subject more fully. Our figure is in strict conformity with the scale on the plate, which is that of an inch. * * * * * * [Illustration: PETROICA _bicolor_. _Black & white Robin._] PETROICA bicolor. _Black and White Robin._ ---- Family Sylviadæ. Sub-family Saxicolinæ. (_See Northern Zoology, Vol. 2._) GENERIC CHARACTER. See No. 8, pl. 36. ---- SPECIFIC CHARACTER. _Black and white. Head, throat, back, and tips of the tail glossy raven black: breast, scapular covers, stripe on the wings, and plumage beneath, white: tail slightly forked._ ----