18 _ TOPOGRAPHY OF THE BODY. 
neck” (nucha ; fig. 4, 7), adjoining the hind head; these are otherwise known 
as the cervical region, and the nuchal region, respectively, and both together 
as “the neck behind.” ‘The front of the neck has been, perhaps, unnecessa- 
rily subdivided, and the divisions vary with almost every writer. It will be 
sufficient for us in the present connection to call it throat (Lat. gula, fig. 
4, 37), and jugulum (fig. 4, 3:), remembering that the jugular portion is 
lower, vanishing in breast, and the gular higher, running into chin along the 
under surface of the head. Gruétur is a term used to signify gula and 
jugulum together; it is simply equivalent to “throat” as just defined. 
Though generally fully covered with feathers, the neck, unlike the body 
proper, is frequently in part naked. When naked behind, it is almost in- 
variably cervix that is bare, from interruption of the upward extension of the 
pteryla dorsalis ; as exemplified in many herons. NVucha is rarely, if ever, 
naked except in continuation of general nakedness of the head. Similarly, 
gula is naked from above downwards, as is especially illustrated in nearly 
all the order Steganopodes, as pelicans, cormorants, etc., that have a naked 
throat-pouch; or some vultures, whose nakedness of head extends over 
nucha, and along gula, as if the feathers were killed by over-manuring with 
the filthy substances these birds eat. The condor has a singular ruffle all 
around the neck, of close, downy feathers, as if to defend the roots of the 
other feathers from such consequence. Jugulum becomes naked in a few 
birds, where a distended crop or craw protrudes, pushing apart the feathers 
of two branches of the pteryla ventralis as these ascend the throat. The 
neck is not ordinarily the place of remarkably modified feathers ; they might 
restrict freedom of motion in the neck; to this rule, however, there are 
signal exceptions. Among these may be mentioned here, the grouse family, 
among our representatives of which, the “ruffed” has singular tufts on the 
sides of the neck; the “pinnated” little wing-like feathers there, covering 
bare, distensible skin, and the “cock of the plains” has curious, stiff, scaly 
feathers ; unless these rather belong to pectus. Cervix proper almost never 
has modified feathers, but often a transverse coloration different from that of 
the rest of the upper parts ; when conspicuous, this is called “cervical collar,” 
to distinguish it from the guttural or jugular “collars” or rings of color. 
Nucha is frequently similarly marked with a “nuchal band ;” often, special 
developments there take the form of lengthening of the feathers, and we 
have a “nuchal crest.” More particularly in birds of largely variegated 
colors, guttur and jugulum are marked Jengthwise with stripes and streaks, 
of which those on the sides are apt to be different from those along the 
middle line in front. Jugulum occasionally has lengthened feathers, as in 
many herons. Higher up, the neck in front may have variously length- 
ened or otherwise modified feathers. Conspicuous among these are the 
ruffs, or tippets, of some birds, especially of the grebe family, and, above 
all our other birds, of the male ruff (Machetes pugnax). But these, and a 
few other modifications of the feathers of the upper neck, are more con- 
veniently considered with those of the 
