Fig. 2 Prairie Chicke 



(Tympanuckus a. americanus) Male. Reproduction of a photograph made by Mr. Geo. E. 

 Moulthrope of Bristol, Conn., who mounted the specimen. 



Tympanum is Latin (tumpanum Gr.), and 

 means some sort of musical instrument after 

 the order of a tambourine, or perhaps a 

 kettle-drum. In anatomy, it has been applied 

 to the ear drum (tympanum); the latter 

 syllable of the word is from the Greek and 

 means: I possess or I have, the whole 

 referring to the distensible air-sacs in this 

 bird, one on either side of the neck. As is 

 well known, these are featherless and capable 

 of great expansion; it is with these that the 

 bird "drums." A good figure of a prairie 

 chicken of the genus Tympanuchus is here 

 presented in fig. 2; it is from a photograph 

 of a mounted specimen, and was presented 

 to me by Mr. Geo. E. Moulthrope of Bristol, 

 Connecticut; it is T. americanus. 



In some parts of the West, the pin-tail 

 grouse of the genus Pedicecetes are called 

 "prairie chickens," especially in the north- 

 west. In this group there are three sub- 

 species under P. phasianellus; they are all 

 western forms and will be described hereafter. 

 Pedion is the Greek for a plain, and oiketes 

 (Gr.) for an inhabitant, hence we have 

 Pedicecetes as a species of plains-grouse. 



Our list of American grouse is completed 

 by the sage cock or sage hen of the western 

 plains, a single species of the genus Centro- 

 cercus (Gr. Kentron, a prickle or spine, and 

 Kerkos, tail), which will be fully character- 

 ized in the concluding part of the present 

 series, that is, in Part IV. 



To further fix these genera of grouse, the 

 following table will be found to be of some 

 assistance: 



Dendragapus: Size large. Not crested. 

 Well marked naked space on each side of 

 neck capable of inflation, usually covered 

 with special, but not conspicuous, feathers. 

 Feathered to the toes. Tail squarish and 

 generally composed of 20 feathers, rarely 

 16 or 22. Wing over 8 inches. 



Canachites: Size medium. Sexes somewhat 

 different. Not crested. No peculiar 

 feathers on neck or head. Neck without 

 naked spaces, but skin capable of slight 

 distention. Colored, bare space over either 

 eye. Nearly square tail shorter than wing; 

 feathers stiffish and flat; usually composed 

 of 16 feathers; very rarely 14 or 18, but 



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