1892.] NATURAL SCIENCES OF PHILADELPHIA. 359 



ing, spinose-tipped (the spine straight), all connected by a more or 

 less heavy induraent of arachnoid, very fine hairs ; flowers deep red ; 

 segments of the corolla little surpassing the throat; pappus short, 

 the very slender plumes naked at tip, and scarcely dilated. 



Abundant on sand dunes near the sea, iu western California, at 

 San Francisco, and southward to Santa Barbara and the outlying 

 islands. A remarkable and maritime species with which the next 

 has needlessly been confused. 



Carduus caadidissimus. 



Stout, erect, 2 or 3 feet high, densely and permanently white arach- 

 noid-tomentose throughout; leaf-outline as in the last ; heads few, 

 on shorter and stouter peduncles, 2 inches high, but narrower than 

 in the last ; outer bracts of the involucre with dilated and closely 

 appressed base and squarrose rigid linear-acerose spinescent tip, all 

 densely arachnoid-tomentose ; flowers crimson ; pappus an inch long, 

 plumose almost throughout. 



Common on dry hills in extreme northern California, thence south- 

 ward, but in the interior only, though coming out to the seaboard 

 at Santa Barbara. Keadily distinguished from C. occidentalis by 

 its dense white tomentum and very different involucre and pappus. 



Carduus venustus. 



Stoutish, 3 feet high, sparingly branching ; lower leaves unknown ; 

 cauline few and reduced, permanently more or less arachnoid, white 

 beneath ; heads large, 2 inches high and broad, terminating long 

 pedunculiform branches; involucre glabrate, the very numerous 

 bracts with closely appressed base and long, squamose, rigid, green 

 lanceolate subulate and rather abruptly short-spinescent tips; cor- 

 ollas bright crimson, the segments longer than the throat ; j^appus- 

 plumes barbellate above the plumose part, the tips scarcely dilated. 



This belongs to the hills of the inner Coast Range of California, 

 from Vacaville southward. It is our most beautiful thistle, and 

 appears to have been made a part of the aggregate Cnicus occiden- 

 talis in the Synoptical Flora of Gray, though it is more strictly an 

 ally of C. Californicus (which is the C. lilacinus Greene, Bull. Calif. 

 Acad, ii, 404 = Carduus Californicus). 



Carduus undulatas Nutt., Gen. ii, 130. 



This very widely disseminated thistle of western North America, 

 is either excessively variable, or else an aggregate embracing many 

 species. The original station for it, as a specific type, is " calcareous 



