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differs in being spicate instead of racemose, while the indi- 
vidual flowers, instead of persisting, fall away easily and 
early, perhaps before the fruit is fully matured. 
The only specimens known were found growing in moss 
below Sixty mile Creek, by J. B. Tarleton, August 3, 1899, 
no. 1754. 
Family SANTALACEAE. 
Comandra livida Richards. Dawson (Williams); Lake 
Bennett (Tarleton). 
Family CARYOPHYLLACEAE. 
Silene repens Patrin. Dawson; Walker Gulch (Wil- 
liams); Ft. Selkirk (Tarleton). 
Silene Williamsii Britton sp. nov. 
Related to S. Menziesizt Hook. Viscid-pubescent all over ; 
stem 1-3 dm. high, the slender branches widely ascending. 
Leaves lanceolate to ovate-lanceolate, sessile, firm, entire, 
2-3 cm. long, 5-10 mm. wide, acuminate at the apex, nar- 
rowed at the base; cymes terminal, few-flowered; pedicels 
filiform, 5-10 mm. long; calyx urceolate, its teeth about 2 
mm. long, erect, the whole about 8 mm. long; petals 
scarcely longer than the calyx. 
Dawson, R. S. Williams, July 14, 1899 (type); fifty miles 
above Stewart River (Tarleton). 
Lychnis trifora R. Br. Stream by West Dawson (Wil- 
liams). 
Vaccaria Vaccaria (L.) Britton. Dawson, introduced 
(Williams). 
Cerastium arvense L. Lebarge Island (Tarleton). 
Cerastium vulgatum L. Dawson, introduced (Williams). 
Cerastium maximum L. Above Stewart River (Tarleton). 
Alsine borealis (Bigel.) Britton. Dawson (Williams) ; Five- 
finger Rapids (Tarleton). 
Alsine laeta (Richards.) Rydb. Dawson (Williams) ; White 
Horse Rapids (Tarleton). 
Alsine crassifolia (Ehrh.) Britton. Five-finger Rapids 
(Tarleton). 
