ARDEID.K — THE HERONS — NVCTHKRODIUa 



68 



liavo Hcen is on nilult I'lJinaliJ from Mount, ('arnit-l, Illinoir*. Tliiti Hiiciiiiu'n «•«« shot from the tuM, 

 mill II jifrfi'i'tly <K'Vi'lopt'«l i'j,'j,' taken from tliu nvarv ; consiMiucnlly llicrc cun lie no ilonbt iw to the 

 fifX. In this spwiniun tliu iiliinilioous is tiiron;;liout of u ileal', fnii' f,'niyisli-lilut' tinj,'e ; tlic rec- 

 triL't'K, even, are <larlc hlnisli i>liinilK'ous (willi u faint jji-uun rtllfction in certain ii^,'ilt^), and are 

 .liilinctly lioniered witii |)hunl)eous-l)]ne. Tliis tinu example is nearly matclieil hy \o. 171 IS, 

 National Miisenin, from the Torlii),'as, Florida (spring of IHdO). The opposite extreme is nearly 

 represented liv another udult female, ])ut proliahly a younger binl, from the miuic locnlity, and 

 oliiiiiiied at ahout the Mime time and uncler nearly tlie same circumstances. In this specimen the 

 pliiiiilieous is everywhere much less liluish, and on the hack and lesser wing-coverts is even very 

 mill li oliscurud by ii smoky tinge ; the l)luck stripes of the back mid wings show u very strong 

 lidilli'-green reflection, which is not the ease with other sjujcimens examine.d ; the reclrices are 

 alisoliili'ly uniform slaty idumbeoiis, without paler edges. The head is marked and colored iw 

 usual in fully adult specimens, and the forehead has a slight tinge of ochraccous anteriorly. A 

 specimen from Fort Brown, Texas (iKWi, March I(t), is almost precisely similar. 



All adult, in nuptial plumiige (No. G7!)l!)), from the Talamanca district, Costa Rica, differs 

 from other specimens in full plumage in having several blue-black feuthei-s in the middle of the 

 crown. This specimen is also remarkable for its large size. 



Some specimens, apparently in their second year, resi'inble adults in full jdumage, except that 

 tliey lack the scapular and occiiiital plumes, and that the black of the head, esja'cially underneath, 

 is mixed with white leathers. Nos. istiiiij and (iTiWO represent this stage. As a proof that the 

 brown tinge on the crown of this species has nothing to do with season or sex, init that, on the 

 contrary, if not an entiiely accidental stain from foreign substances, it is rather a mark of im- 

 maturity, it may be stated that both these immature specimens have the ferruginous stain very 

 strongly marked, it being in the former speiiimeii deeper than I have ever seen it in any a<lult, 

 and SI) dark in jdaces as to appear of a dark sepia- or snufT-brown tinge 



A younger stage of plumage than the above, and one which i)erhaiis illustrates a change in color 

 iif the fiifthcrs thi'imi'lnn, irilhout an actual nwult, is represented by No. 118i)2 (Tortugas, April f)). 

 In this, all the well-detined strii)es and streaks of the first stage have become obliterated, but at 

 the same time the sombre cidors of this age are retained. The upi)er i)arts, indiidiii;) the scapiihir 

 lihimiii, which are not only jmsi nt, hut u-dl (h-fiinpal,^ are of a ilark oily, sooty, brownish-gray, 

 with a faint green reflection in certain lights ; many of the feathers darker medially (esju'cially 

 tin- wing-coverts and scapular jiluines), the wing-coverts having well-defined i)ale margins. The 

 fofelicail and middle of the crown are rich brown, of a shade between cinnamon and sepia ; the 

 oiiiput uniform blue-black ; the malar region and throat streaked with blue-blnck nnd white. 

 The lower jiarts much as in the first plumage, but the stripes more indistinct. There ore no 

 occipital ]>lumes. 



From the above, we may reasonably infer that the a.ssumi)tion of the jjcrfect adult plumage is 

 a very gradual proces-s, and not accomplished at a single, nor solely by several moults ; but that 

 after each moult a gradual change in the cidors of the feathers takes jdace, — a fact which is cer- 

 tiiiiily established with regan.! to many birds. Thn>ie specimens in which the plumbeous is of a 

 clear, tine l)luish cast are therefore to be considered* the oldest individuals, and the more sombre 

 ones younger. 



Ill the Cialapagos Islands is found a Nijcth<To(liu!t which is said to be distinct from the common 

 species. This form we have seen only in the immatui-e plumage, a description of which is given 

 iielow.^ 



' It is probable that the species breeds in this plumage. 

 ' NvcTiiKiionius rAiTKii (Sd. k Salv.). 



" Xijcticorax viiilaceus," D.uiwix, Zool. Reng. III. Birds, 1841, 128 (Onlapngos). 

 "Anleii violacM," Si'SDKV. P. Z. S. 1871, 125 ((ialaimgos). 



Ni/clicoraj: jmu/if); Sci,. & S.M.v. 1'. Z. S. May 12, 1870, 323, 327 (Oalnixigos). — Salvin, Trans. 



Zool. Soc. IX. ix. 1875, 498. 



Young i , tratuiilion plumngr : Head chiefly black, unifonn on the sides of the pilcum and occiput, 



the centre of tlio hitter mi.xcd with elongated light-brown featheiu having darker mesial 8trii)es. Stripe 



on side of the head, from the rictus over the ear, light tawny brown ; malar region bluc-hhick, with a 



IVw nan-ow whitish streaks ; chin and throat more heavily streaked with white. Upper parts in general, 



