_Cistothorus_, CABANIS, Mus. Hein. 1850, 1851, 77. (Type, _Troglodytes stellaris_.) _Telmatodytes_, CABANIS, Mus. Hein. 1850, 1851, 78. (Type, _Certhia palustris_.) _Thryothorus_, VIEILLOT, Analyse, 1816, according to G. R. Gray. [Line drawing: _Cistothorus palustris._ 1454 ♂] GEN. CHAR. Bill about as long as the head or much shorter, much compressed, not notched, gently decurved from the middle; the gonys slightly concave or straight. Toes reaching to the end of the tail. Tarsus longer than the middle toe. Hind toe longer than the lateral, shorter than the middle. Lateral toes about equal. Hind toe longer than or equal to its digit. Wings rather longer than the tail, all the feathers of which are much graduated; the lateral only two thirds the middle. The feathers narrow. Back black, conspicuously streaked with white. Of this genus there are two sections, _Cistothorus_ proper and _Telmatodytes_, the diagnoses of which have already been given. The two North American species present the feature, unique among our Wrens, of white streaks on the back. A. Cistothorus. Bill half length of head. No white superciliary streak. Head and rump and back streaked with white. Tail dusky, barred with brown … _C. stellaris._ B. Telmatodytes. Bill length of head. A white superciliary stripe. Back alone streaked with white. Tail-feathers black, barred with whitish … _C. palustris._ Cistothorus stellaris, CABAN. SHORT-BILLED MARSH-WREN. _Troglodytes stellaris_, “LICHT.” NAUMANN, Vögel Deutschlands, III, 1823, 724 (Carolina). _Cistothorus stellaris_, CAB. Mus. Hein. 77.—BAIRD, Birds N. Am. 1858, 365; Rev. 146.—SCLATER, Catal. 22, no. 142 (in part). _Troglodytes brevirostris_, NUTT. Man. I, 1832, 436.—AUD. Orn. Biog. II, 1834, 427, pl. clxxv.—IB. Birds Am. II, 1841, 138, pl. cxxiv. _C. elegans_, SCLATER & SALVIN, Ibis, 1859, 8. SP. CHAR. Bill very short, scarcely half the length of the head. Wing and tail about equal. Hinder part of the crown and the scapular and interscapular region of the back and rump almost black, streaked with white. Tail dusky, the feathers barred throughout with brown (the color grayish on the under surface). Beneath white; the sides, upper part of breast, and under tail-coverts reddish-brown. Upper parts, with the exceptions mentioned, reddish-brown. Length, 4.50; wing, 1.75; tail, 1.75. HAB. Eastern Province of United States, west to Loup Fork of Platte. There is a closely allied variety from Mexico and Guatemala (_C. elegans_, SCLATER & SALVIN, Pr. Z. S., 1859, 8) which differs in the characters stated below.