INTRODUCTION. 



25 



diminish iu size until they reach their limit on the coast about opposite Kadiak Island. This larj^e 

 island is included within the present district, and forms its western boundary. Strangely enough, 

 although the eastern part of Kadiak is heavily wooded, the western part of the island is destitute 

 of trees. The climate is somewhat drier and the winters colder in the Kadiak portion than else- 

 where iu the district. 



The forests are almost wholly coniferous, and the Abies sitkcnsis, A. mertensiana, A. canadensis, 

 and Piniis contorta are generally distributed and form the great bulk of the trees. In the region 

 about Sitka and southward, the yellow cedar, Ciipressus nutlatensis, is a striking and handsome 

 tree of great size, reaching 100 or more feet in height and 5 or G feet through at the base. 



Taking the climate of Sitka as typical of this district, and bearing in mind that it becomes 

 milder to the south and drier and colder to the north and west, we have, as the results of nearly 

 fifty years' observations by the Eussians, the following data : The maximum temperature during 

 this period was + 87°, with a minimum of — 4°, the mean annual temperature being 43°.28. The 

 mean annual rainfall during this period was over SO inches, with the record for one year reaching 

 103 inches. The mean annual number of days on which rain and snow fell was 198, and it varies 

 from 190 to 285, according to Mr. W. H. Dall. 



To show the seasonal distribution of these factors I subjoin a table giving means for observa- 

 tions taken at Sitka during fourteen years between 1849 and 1862, inclusive : 



XOTE.— All of the temperatures in this report are Hceording to Fahrenheit. 



The enormous precipitation upon the seaward face of the mountains along this coast has pro- 

 duced a large series of some of the finest glaciers in the world, which extend to the sea in many 

 of the bays. The effect of this damp climate and heavily-wooded region upon the animal life 

 found there is so well known, as illustrated on thecoastof Washington and Oregon, that it scarcely 

 needs mention here. All of the colors of the birds and mammals resident here are intensified and 

 are darker than those shown by the same or allied species resident elsewhere. Pale browns be- 

 come rich rufous, or rusty-red, and grays become dark brown, with corresponding changes in other 

 colors. The red on Pinicola enucleator and Acanthis linaria, in resident examples, is more intense; 

 enough so to nearly produce recognizable races. 



It is a well-known fact to fur traders that the furs of animals killed iu this district are much 

 darker or more intensely colored than elsewhere in the Territory. This holds good with both cin- 

 namon and black bears, besides other species. 



Sciurus hndsonhis donglassi is the most familiar and striking example of this intensity of col- 

 oration. SpermopMhis empetra lodiacensis, described from Kadiak specimens and not known from 

 other parts of the Territory, has the top of the head and middle of the back a much darker shade 

 of brown than is exhibited by typical empetra, which occupies most of the surrounding region. 

 Curiously enough, lodiacct^sis exhibits, at the same time, a much paler or grayer color on the 

 sides and below than is shown by empetra. 



Among the birds of this district the effects of climatic iutiueuce are even more marked than 

 among the mammals. In the following list are named the species showing this most plainly: 

 Turdus aonalaschlcv, T. nstulatus, Parus rvfescens, Troglodytes hiemalis pacificus, Leucosticte 

 tephrocotis littoraUs, Melospiza fasciata rvjina, Passerella iiiaca nnalaschensis, Gyanocitta stelleri, 

 Megascops asio l-ennicottii, Bubo rirginianus satnratus, Acclpiter atricapiUus striatulus, Ben- 

 dragapus obscurus fulighiosiis, Bonasa umbelhts sabmi, with Acanthis linaria and Pinicola enucleator, 

 in which the intensification of color is apparent but not suflBcient to warrant separation from the 

 typical form. In addition to the foregoing species the following birds are only found in the Sitkan 

 S. Mis. 15(3 4 



