5 o THE CONDOR [ Vol. IV COMMUNICATIONS. QUESTIONS OF THE DAY? of D, and in like manner suppose a develop- Some months ago editorial comment was made in the CONDOX? (July-August ?9oo, p. 95) on a 'valuable service to ornithologists whose lots are cast in the San Francisco Bay region, referring to the recognition by name of certain birds of this region which are intermediate in character between those found to the north and south respectively. From the standpoint taken, which seems to be one for convenience in labeling specimens, this 'solution of the difficulty' might commend itself to collectors in that region providing they never received specimens from their fellow collectors a little to the north or south, and to these latter it would be a more or less questionable boon un- der any circumstances. In case the ornitholo- gists of the San Francisco Bay region should desire to attach names to the birds found not more than xoo miles either north, south or east of them they would find that this supposed la- bor-saving device had multiplied their troubles ins, read of simplifying them. Moreover, an additional name in a group of this kind rather tends to obscure the relationships of the forms than otherwise. To one who has seen no spec- imens whatever the binomial Chaineva fasci- ala and the trinomial Uhamcea ? phcea would indicate "an unbroken gradation from one to the other," exactly what admittedly exists. Thus if two names indicate the facts it would not seem to be more convenient to have three. Under different circumstances however it is conceivable that even with no greater difference between the extremes it might be advisable to adopt several names in order to represent the facts; and this also even if the respective de- grees of difference were slight and difficult to determine. To illustrate, let the lines A, A ?, B, C, D, E, F, and G in the accotnpanying diagram repre- sent the intensity of a variablecharacterof any two animals at various points in their develop- ment and the lines A C and A F the extent of the animals' distribution. In one ease sup- pose the salient character or characters to have developed uninterruptedly from condition A to condition C and these extremes recognized by name; then suppose in another case a develop- ment frcm A to D, after which there is a con- stant condition front D to E with the intensity
- See Bird Lore, ?t?, 38-39, Jan.-Feb. x9ot.
ment from E to G and thence constant to F. In this case although the intensity of F does not exceed that of C it seems that the facts can be best represented in nomenclature by three names instead of two and although the inten- sity of B and D are equal it would be advisable to recognize D in nomenclature, while.it Would serve no useful purpose, as far as present know- ledge goes, to treat B in the same manner. This is theory. The real conditions are of course much more involved than any simple diagram can indicate; nevertheless the rapid increase of collections and knowledge of physi- ographic conditions constantly contribute to the elucidation of problems of this sort. Such questions certainly appear in the study of groups of mammals and possibly to a slighter degree in the study of birds. Cert- ainly a name is unnecessary for a condition which represents neither of two ex- tremes nor a special development of either, but merely a point between them on either side of which is a progressive development in opposite directions. And furthermore, degree of differ- ence is not the sole criterion for the applica- tion of names; and the fact that a species or subspecies is difficult to identify is not alone a reason for withholding a name. A lazy 'lay' ornithologist oran ignorant one might contend that, since it requires care and experience to distinguish some species of Empidonavc, it would be most convenient to 'lump' them. As a matter of fact there have been very few subspecies de- scribed which are as difficultof discrimination as the species Empidonavc rainlinus and E. lrailli alnorum. The tendency to revolt among the 'lay' class against the so-called'splitting seems to be not so much because it is thought to be based on unsound principles, but more because it brings abou[a multiplication of names which are hard to remember and because it makes the identification of individual specimens diffi- cult. The popular ornithologist, following in the footsteps of other popular scientists, has reached the point where he cannot keep. pace with the man who gives up his life to technical work. There was a time when country gentle- men of the Gilbert White type were able to keep fairly abreast of all branches of natural science, but now to be expert in any one branch requires almost a lifetime of study. The question then arises--is this a deplorable condition, or is it the natural outcome of a vast increase in quantity and quality of material, a corresponding increase in facilities for work, and a convenient access to useful contributive results of investigations in other branches of science? Is it strange that the careful orni- thologist should continually add nanted and
