70 P« ^ ax - — Euphorbiaceae-Acalypheae-Chrozophorinae. 



2 8. D. serrata (Torr.) Heller, Gat. Northam. pl. (1900) 5. — Aphora serrata 

 Torr. Bot. U. S. Mexic. Bound. (1858) 197. — Argyrothamnia serrata Müll. Arg. in 

 Linnaea XXXIV. (1865) 147; in DG. Prodr. XV. 2. (1866) 739. — Argythamnia 

 serrata Wats. in Brew. et Wats. Bot. Californ. II. (1880) 69. — Annua, dz 20 — 25 cm 

 alta, a basi ramosissima; ramuli villoso-pubescentes, vix glabrescentes, subteretes, cinereo- 

 lutescentes. Petiolus 2 — 5 mm longus; limbus 12 — 25 mm longus, 7 — 12 mm latus, 

 ovatus vel obovatus, emarginatus vel obtusus, basin versus in petiolum cuneato-angustatus, 

 inferne integer, antice irregulariter denticulatus, membranaceus, pilis elongatis, mal- 

 pighiaceis villoso-pubescens, non glabrescens, basi trinervius ; costae parum prominentes. 

 Racemi 5 mm longi, abbreviati, flores Q 1 — 2, deinde tf 2 — 4 proferentes; rhachis 

 villosa; bracteae lanceolatae, acutae, 1 y 2 mm longae; pedicelii brevissimi, fructigeri non 

 accrescentes. Sepala rjf 1 5, lineari-lanceolata, acuta, 2 mm longa, extus villosa, intus 

 glabra, hyalina; petala rhombeo-lanceolata, acuta, ealycem aequantia vel paulo superantia, 

 extus secus costam villosa, intus glabra, nervo medio basi paulo incrassata, columnae 

 vix adnata; disci glandulae liberae, lineares, apice attenuatae, superne membranaceae, 

 glabrae; stamina 10, biverticillata ; staminodia nulla. Sepala § 2V2 — 3 mm longa, 

 lanceolata, acuminata, hyalino-marginata, extus villosa, intus glabra ; petala ut in flore q 1 , 

 sed 2 mm longa; disci glandulae liberae, ovoideae, glabrae; ovarium pilis malpighiaceis 

 elongatis, stylos occultantibus densissime villosum; styli ad 1 / 3 longitudinis connati, 

 parte libera ad medium bifidi, lobi apice clavato-incrassati. Capsula 4 mm lata, villosa. 

 Semina subglobosa, apiculata, minute aspera, 1 */ 2 mm diametientia. — Fig. 1 4 D. 



Mittelamerikanisches Xerophytengebiet: Kalifornien, Colorado-Tal, Fort 

 Yuma (Schott), Williams River (Palmer), Rio Gila (Parry). — Mexiko, Sonora, 

 am Golf von Kalifornien (Pringle!). 



Nota. A. Rose et Standley nuperrime descripscrunt speciem novam [D. odontophyllam 

 in Contrib. U. St. Nat. Herbar. XVI. (1912) 12], nobis ignotam, quam fide descriptione autorum 

 a D. serrata distinguere non possumus. Planta crescit in Mexiko, Sonora, Papago Truks 

 (Mc. Dougal n. 36). 



29. D. californica Pax et K. Hoflm. n. spec. — Argithamnia californica Brandegee 

 in Sched. — Annua, omnino glabra, patentim ramosa, satis distanter foliosa. Petiolus 

 10 — 15 mm longus, filiformis; limbus 3 — 4 cm longus, 12 — 15 mm latus, lanceolatus 

 vel oblongo-lanceolatus, acutus, basi in petiolum attenuatus, minute glanduloso- denti- 

 culatus, membranaceus, basi trinervius, saepe junior purpurascens; stipulae filiformes, 

 2 mm longae, pallidae. Racemi valde abbreviati, congestiflori, basi florem Q unicum 

 et rf 2 — 4 gerentes; rhachis 2 — 3 mm longa, cum omnibus partibus glabra; bracteae 

 2 mm longae, ovatae, acutae, hyalinae, nervo viridi percursa; pedicelii (jp brevissimi, 

 Q 1 — 2 mm longi. Sepala (j 1 2*/ 2 mm l° n g a > lanceolata, obtuse acuminata; petala 

 calycem aequantia, ovata, longe et acute acuminata, alba, hyalina, columnae breviter 

 adnata vel libera; disci glandulae liberae, oblique fusiformes, majusculae; stamina 10, 

 biseriata; verticilli approximati; staminodia 3, minuta. Sepala Q lineari-lanceolata, 

 acuta, 5 mm longa, albo-marginata et glanduloso-denticulata; petala calycis dimidiam 

 aequantia, alba, hyalina, breviter unguiculata, rhombeo-ovata, longe cuspidato-acuminata; 

 disci glandulae parvae, quadratae; ovarium glabrum; styli liberi, ultra medium bifidi, 

 lobi vix incrassati. 



Westamerikanische Wüsten- und Steppenprovinz : Kalifornien, Colorado- 

 Wüste im Riverside Co., Marshall Canon (Hall n. 5796!). 



Nota. Glabritie omnium partium ad D. Brandegei accedit, cujus flores 5-andri des- 

 cribuntur. 



30. D. neomexicana (Müll. Arg.) Heller, Cat. Northam. pl. (1900) 5. — Aphora 

 humilis Torr. Bot. U. S. Mex. Bound. (1858) 196. — Argyrothamnia neomexicana 

 Müll. Arg. in Linnaea XXXIV. (1865) 147; in DC. Prodr. XV. 2. (1866) 739.— Caules 

 e rhizomate lignoso plures, 10— -20 cm longi, prostrati vel arcuato-adscendentes, sim- 

 plices, pilis malpighiaceis elongatis villosuli. Petiolus 2 — 4 mm longus; limbus 1 */ 2 — 

 2y 2 cm longus, 6 — 11 mm latus, lanceolatus vel obovato-lanceolatus, acutus, basi in 



