8 NOr.TII AMKIilCAN" lilUDS. 



inaritinio portions of llio I'liitL'd States, tlio Europoan roprosoiitativcs of both 

 species lifiiig ^ncnerally disliilmteil tliroiinhout lliat etjiitinent. On the other 

 hand, the northwest-coast race of onr ^ro/m astu (S. l-t'iiniivtti) seiMiis to be 

 nearly identical witii tiie Japanese S. acini foi'ijiirs (.Sehlegel), which is iin- 

 donlitedly relerrihle to tlie same sjiecies. 



As r(';4ai-ds their ]iluina,ii;e, the Owls did'er most remarkably from the 

 Hawks in the fact that the sexes are invarialdy colored alike, while from 

 the nest to perfect maturity there are no well-marked i)roj,'ressive staj^es 

 distin.ifuishin^' tlie dill'erent ayes of a s]iecies. The nestlin<,', or downy, 

 ]>luniag(', however, of many species, has the intricate pencillii;,L;' of the adult 

 dress I'ejilaced by a simjjle transverse barring upon the imperfect downy 

 coverinj,f. The downy young of XjU'tca scumliava is jdain sooty-brown, and 

 that ui titii.r Jldiitmm immaculate wliite. 



In many species the adult dress is cluiracterized by a mottling of various 

 shades of grayish mixeil with ochraceons or i'ulvons, this ornamented by a 

 variable, oi'ten very intricate, pencilling of dusky, and more or less mixed 

 with white. As a conse(iuence of the mixed or mottled character of the 

 markings, tlut plumage of the Uwls is, as a rule, dilHcult to descril^e. 



In the variations of plumage, size, etc., with dill'erences of habitat, 

 there is a wide range, the nsually recoginzed laws ^ ai)]ilying to 'most of 

 those sjiecies which are generally distributed and resident where breeding. 

 Of the eight .species eonnnon to the J'ahearctic aiul Nearctic Realms, all but 

 one {Vtiis bntr/(//(ifiis) are modified so as t(j form representative geographical 

 races on the two continents. In each of these cases the American bird is 

 nuich darker than the Kuro]iean, the brown areas and markings being not only 

 more extended, but dee])er in tint. The dilferenee in tliis respect is so tan- 

 gible that an experienced ornithologist can instantly decide to which con- 

 tinent any s])ecimen behjngs. Of tlie two cosmopolitan sjjecies one, Otus 

 ?/m(7///(//«>', is identical throughout; the other is modiiied into geographical 

 races in nearly every well-marked province of its habitat. Thus in the 

 Taliearctic Itealm it is typical Stri i: flammi'a ; in the Xearctic Iicalm it is var. 

 2)n(tincoln : while Tro]iical vVmerica has at least three well-marked geo- 

 graphical races, the species being reiiresented in Middle America by the var. 



ditiivly ivstrictoil to the western ]imtioii, or else are iinuli more iil)Hii(l;iiit there tliiin in the 

 cast. Tlie Iviropean e-,.,iera I'iiirhis, C.cca/linrii.ili-.t, Xiiri/r(i(jii^>md C<ih(inha liave reiiri'.sfnta- 

 tives imlv in the western portion of Xortii America. 



inslanc.'s of a similar relation l)etw<'eu tlie plants of the Western Trovince of North .America 

 and those of Europe, ami more strikiMR likeness hctwceii the ihira of the Eastern Itcgion ami 

 tliat of Eastern Asia, aiv lieautinilly I'xplaiiieil in rrol'essor dray's interesting and instructive 

 liajicr entitled "Seipioia, and its History," an address delivered at the mcctiiij; of the American 

 A.ssoi'iation for the Advancement of Science, at Diilimine, Iowa, Anf;iist, 1>h7± The poverty in the 

 si'ceies of tortoises, ami richness in li/ards, and the lieciiliarities of the ichtliyolo,i,'ical fauna, as well 

 as aliseiiceof forms of Western North America and Europe, comiiarcd with Eastern North America 

 and Eastern Asia, all'ord other exaiii|iles of ])arallclisiii in other classes of the Animal KiiiRdom. 



' Sec r>ainl. Am. .louni. Arts and Sciemvs, V(d. XM, .Ian. and jMarcli, ISOU ; Allen, Bull. 

 Mns. Comp. Zobl. Caniliiiduc, Vol. II, No. 3 ; and Hidfjway, Am. Journ. Arts and Sciences. 

 Vols, IV and V, Dec, 1S7-.', and Jan., 1S7;!. 



