HABITS. According to Mr. Ridgway’s observations, the _P. megalonyx_ replaces in the Rocky Mountain region and in the greater portion of the Great Basin the _P. arcticus_ of the Plains, from their eastern slope eastward to the Missouri River, and the _P. oregonus_ of the Northern Sierra Nevada and Pacific coast. It is most nearly related to the latter. He became familiar with the habits of this species near Salt Lake City, having already made like observations of the _oregonus_ at Carson. A short acquaintance with the former, after a long familiarity with the latter, enabled him to note a decided difference in the notes of the two birds, yet in their external appearance they were hardly distinguishable, and he was at first surprised to find the same bird apparently uttering entirely different notes, the call-note of _P. megalonyx_ being very similar to that of the common Catbird. The song of this species, he adds, has considerable resemblance in style to that of the eastern _P. erythrophthalmus_, and though lacking its musical character, is yet far superior to that of _P. oregonus_. This bird is also much less shy than the western one, and is, in fact, quite as unsuspicious as the eastern bird. Nests, with eggs, were found on the ground, among the scrub-oaks of the hillsides, from about the 20th of May until the middle of June. This species has been obtained on the southern coast of California, and through to the valleys of the Gila and the Rio Grande. In California it was obtained near San Francisco by Mr. Cutts and Mr. Hepburn; at Santa Clara by Dr. Cooper; at Monterey by Dr. Canfield; in the Sacramento Valley by Dr. Heermann; at San Diego by Dr. Hammond; at Fort Tejon by Mr. Xantus; at Saltillo, Mexico, by Lieutenant Couch; in New Mexico by Captain Pope; and at Fort Thorn by Dr. Henry. Lieutenant Couch describes it as a shy, quiet bird, and as found in woody places. Dr. Kennerly met with this bird at Pueblo Creek, New Mexico, January 22, 1854. It first attracted his attention early in the month of January, in the Aztec Mountains, along Pueblo Creek. There it was often met with, but generally singly. It inhabited the thickest bushes, and its motions were so constant and rapid, as it hopped from twig to twig, that they found it difficult to procure specimens. Its flight was rapid, and near the ground. Dr. Cooper speaks of this species as a common and resident bird in all the lower districts of California, and to quite a considerable distance among the mountains. It was also found on the islands of Catalina and San Clemente, distant sixteen miles from the mainland. Though found in New Mexico, Dr. Cooper has met with none in the barren districts between the Coast Range and the Colorado, nor in the valley of the latter.