530 PROCEEDINGS OF THE AMERICAN ACADEMY. 



ZALUZANIA, Pers. Heads (medium-sized) heterogamous with obvi- 

 ous rays or iu one species homogamous and discoid. Involucre hemispher- 

 ical; bracts 1-3-seriate, linear to ovate, appressed, subequal. Receptacle 

 conical ; pales couduplicate : ray-flowers uniseriate, few to many, stylif- 

 erous and fertile, rarely wanting: disk-flowers regular, perfect, fertile ; 

 the tube usually slender and pubescent, tending to expansion over the 

 summit of the acheue ; the subcylindric throat of about equal length ; 

 limb of 5 ovate or triangular acute teeth. Anthers unappendaged at the 

 base. Style-branches obtuse or with a short acute appendage. Achenes 

 of the disk-flowers somewhat flattened ; j^appus none ; achenes of the 

 ray-flowers 3-gonal, sometimes crowned with a few deciduous scales. — 

 Syn. ii. 473 (1807); DC. Prodr. v. 553; Benth. & Hook. f. Gen. ii. 

 362; Hoffm. in Engl. & Prantl, Nat. Pflanzenf. iv. Ab. 5, 233. Chili- 

 ophyllum, DC. 1. c. 554. Hybridella, Cass. Diet. xxii. 86. Ferdinanda, 

 Lag. Elench. 31. Chrysopluinia, Kunth in Less. Syn. Comp. 224. — 

 Twelve species extending from Arizona to South Mexico and (?) Central 

 America. 



Subg. 1. Hybridella. Palustrine perennial herbs: leaves 3-4- 

 pinnatifid : disk globose, large, 1.2 to 1.6 cm. in diameter; pales very 

 narrow: rays oblong-linear, yellow, numerous (20 to 30), irregularly 

 bifid at the apex. — Hybridella, Cass. Bull. Soc. Philom. 1817, p. 12, & 

 Diet. xxii. 86. Chiliophrjllum, DC. Prodr. v. 554. 



1. Z. GLOBOSA, Sch. Bij). Decumbent, hirsute : stems 3 dm. high, 

 bearing 3 to 5 leaves and about 6 long-peduncled heads : radical leaves 

 several, 1 to 1.5 dm. long, 4-pinnatifid, the ultimate lobes lance-linear, 

 acute, 2.5 to 3.5 mm. long: cauline leaves similar, oblong in general con- 

 tour, the margined petioles copiously ciliate or even lanate near the base: 

 involucral scales lanceolate, acute. — Flora, 1861, p. 564; Hemsl. Biol. 

 Cent-Am. Bot. ii. 159, excl. pi. Hartw. and syn. in part. Anthe7nis 

 globosa, Ort. Dec. 46 ; Jacq. Hort. Schoenb. iii. t. 372 (cited in text as 

 371). Chiliophyllum globosum, DC. Prodr. v. 554. — Swamps, low 

 meadows, &,c., San Luis Potosi, Parry & Palmer, no. 527 ; Valley of 

 Mexico, Bourgeau, no. 385, Schajfner, no. 80, Pringle, nos. 2925, 3204 ; 

 Mexico, without locality. Pates, Schmitz, no. 46. 



2. Z. MYRiOPHTLLA, Sch. Bip. 1. c. 565. Identical in habit, pubes- 

 cence, and floral characters with the preceding: leaves also oblong in 

 contour, the cauline about 4; ultimate segments very small (2 mm. long 

 or less, and 0.8 to 1 mm. wide), rounded at the apex. — Z. globosa, 

 Hemsl. 1. c. in part. — Aguas Calientes, Hartweg, no. 111. Type num- 



