28 THE CONDOR Von. VII Myiarchus m. magister. Arizona Crested Flycatcher. On the cactus covered hill north of our camp we found this species breeding quite abundantly, though none were seen out on the flat mesa; and had we remained in our camp in the mesquites, scarcely five hundred yards distant from the hill, I doubt if we would have known there were any of the birds around, so closely did they stick to their barren hillside. The birds were exceedingly noisy and quarrelsome, but very wary and hard to get a shot at, sitting at a safe distance when their nest was robbed, and uttering continually their loud, harsh call. Some eight or ten nests were examined, all very much alike. The cavities were all from fifteen to twenty- five feet from the ground, and I doubt that we found any nests more than half way up the hill. Most of the species occupying the cactuses were found nearer the base than the summit of the hill. The nests were all very much alike, being com- posed mainly of hair taken from dead horses and cattle, and smelling vilely. Usu- ally there were pieces of snake skin in the nests, and occasionally a mummified owl or woodpecker underneath. The number of eggs in a set ranged from three to five. Myiarchus cinerascens. Ash-throated Flycatcher. Breeds fairly abundantly in the mesquites. I have also found it nesting in the giant cactus, but not in any numbers. Empid0nax trailli. Traill Flycatcher. Seen and heard in the mesquites along the river. Pyr0cephalus r. mexicanus. Vermilion Flycatcher. A common and conspic- uous species, breeding everywhere in the mesquites. (To be concluded.) A New Code of Nomenclature URING the latter part of the fall semester of I9O4, President Jordan of Stanford Univer- sity delivered a series of lectures on nomenclature before the faculty and graduate students of the biological departments. After an introductory talk on the history of nomenclature, he devoted the remaining lectures to a discussion of the principles and canons of the A. O. U. Code. On several iraportant points Dr. Jordan took issue with the?e. It is fortunate for students in general that Dr. Sotdan's wide practical experience with knotty problems in noraenclature is to be embodied in a new code, which will shortly appear under the joint authorship of Doctors Jordan, Evermann, and Gilbert. Dr. Jordan has kindly allowed me to make extracts ?rora the manuscript, in advance of the regular publication. There are thirty canons in the new code, several of the A. O. U. canons having in raany cases been condensed into one. These are followed at the end by short notes. Most of the canons of the A. O. U. code are now very generally accepted and need no explanation. I have made extracts only where the new code differs materially from that of the A. O.U. The paper is entitled "NOMENCLATURE IN ICttTHOLOG. A PROVISIONAL CODE BASED ON THE CODE OF THE AMERICAN ORNITHOLOGISTS' UNION." "The recent preparation of numerous papers in systematic ichthyology has necessitated the reconsideration of many problems of zoological nomenclature, and as some of these are not cov- ered by any canon in any recognized code,,and again, as certain canons in the best considered of the various codes of nomenclature, that of the American Ornithologists' Union, are not available in the study of fishes, we have ventured to draw up a code for our own use in ichthyology. "The value of a code depends not on the authority behind it, but solely on its simplicity, use- fulness, and naturalness. Formal agreements amoug groups of authors are always marked by compromises in which fitness and exactness are more or less sacrificed in the interest of unanim- ity of action. These compromises one and all are discarded in the progress of science. "The present statement represents therefore solely the present practice of the present authors. No one else is bound by it, and they will not be bound in the future in any case in which they find reason to believe that their present views are faulty. "The different canons in this code are based on those composing the code of the American
