72 PROCEEDINGS OP TUE AMERICAN ACADEMY 



Lactdca. Of genuine Lactuca, or the Scariola section, we appear 

 to have five indigenous species, namely: L. Canadensis, L., the oldest 



only a depauperate variety of tliis. — Var. pukpureum, Macrorlu/nchus purpureus, 

 Gray, 1*1. i-'eiidl. 114, appears to be only another form of this species. 



T. GKACiLEKS, Gray, and var. ? Gulenei. Vide supra. 



++ ++ Flowers yellow. 



T. NuTTALLii, Gray, Proc. Am. Acad. ix. 210, & Bot. Calif, i. 408, excl. pi. 

 Nevius. To this I should refer the ambiguous forms from tlie Sierra Nevada, 

 which were placed in T. auranliacum, but whicli are near to T. (jlaucum. 



T. AP.vRGioiDES, Less, in Linnaja, vi. 594. A small species, restricted to the 

 coast of California. The following species has been confounded with it, the 

 confusion beginning with Hooker and Arnott, in Bot. Beechey. 



+- t- Beak slender-filiform, twice to four times the length of the short-fusiform 

 or oblong (about 2 lines long) akene: pappus soft and fine, rather flaccid: 

 flowers all yellow. — Slijlopappus, Nutt. 



++ Pappus (whitish) about the length of the beak, and only about double the 

 length of the akene : head from half an inch to barely an inch high : ligules 

 elongated : involucre villous-pubescent. 



T. iiUMiLE. Borkhausia Lessingii, & Macrorhjnchus Lessinf/ii, Hook. &, Am. 

 Bot. Beech. 145, & 361, excl. syn. ; for it is not Lessing's T. upanjioides by the 

 character. Macrorhijnchus humile, Benth. PI. llartw. 320, a smiiU form. M. Ilm- 

 fordii, Kellogg, Proc. Calif. Acad., a larger form. Common near the coast, from 

 Monterey, California, to Oregon. 



■w- ■»-*■ Pappus (bright white) much shorter than the more elongated and capil- 

 lary beak : ligules short. 



T. LACiKiATUM. Glabrous or with some soft loose pubescence : closed head 

 of fruit not over an inch high : akene 2 and beak 5 to 7 lines long. — Slijhpappus 

 laciniatus, Nutt. (specimens too young and small), & var. lonrjifollus, Nutt. 1. c. 

 Troximon fjrandijlorum, var. tenuifolium &, var. lacinialum. Gray, Bot. Calif. 1. c. — 

 Common from Oregon to Brit. Columbia, and a form of it in California, which 

 too nearly ajiproaches the next. 



T. GRANDiFLORUM, Gray, 1. c., with syn. ; excl. vars. Leaves liirsutely or 

 cinereous-puboscent, or glabrate : scapes stout: involucral bracts more imbri- 

 cated, lanate or tomentosc when young; fruiting head commonly an inch and a 

 half high : akenes 2 and beak 6 to 8 lines long. 



# * Perennials: akenes abruptly very long-beaked from a truncate summit. 



T. RETRORSCM, Gray, 1. c, with syn. 

 » « * Annuals, small, occasionally subcaulescent : beak of akenes filiform and 



long. — Mdcroilii/nrh'ts, Less. Syn. 139, but akene not at all " plano-obcom- 



pressum." Kijmapleura & Cri/ptopleura, Nutt., 1. c. 



T. nETEROPiiYLLUM. T. Clillense, Gray, Bot. Calif. 1. c. Macrorhynchus 

 Ckilemia, Hook. Lond. Jour. Bot. vi. 25G, but not of Less. M. lu-tcmpliijUus & 

 3/. Ccdi/ornlciis, Torr. &, Gray. Varies much in the akenes, &c. ; pretty clearly 

 distinguished from the Chilian plant or plants, by the erect involucre not villous, 

 and shorter outer bracts. Outer akenes sometimes pubescent or villous, not 



