OF ARTS AND SCIENCES: MAT 30, 1865. 549 



long, mostly opposite ; the lower oval or oblong, minute. Doubtless 

 this plant grows larger, but probably still remains different from the 

 following species in its much obcompi-essed and broad achenia, the 

 summit rounded and entirely destitute of any beak. Involucre, as in 

 the other species, hispid-glandular on the back, completely enclosing 

 the achenia. 



Hemizonia (Hemizonella) parvula: bi-tripoUicaris, pilis albi- 

 dis magis hispida; caule patentim ramoso; fohis angusto-linearibus, 

 superioribus capitula sessilia involucrantibus eaque longe superantibus ; 

 acheniis glaberrimis angustis fusiformi-falcatis subtrigono-obcompres- 

 sis, rostro brevi incurvo. — EHamath Valley, Oregon, Mr. Kronkite. 

 Leaves half an inch to an inch long, half a line wide. It is this species 

 which by the achenia most approaches the genus Harpcecarpus, but 

 these are still decidedly obcompressed instead of compressed ; and it 

 would be very inconvenient now to admit compressed and obcompressed 

 achenia into the same genus. Obviously these Uttle plants are much 

 reduced Hemizonice. 



Hemizonia (Hemizonella) Durandi: caule a basi ramoso 

 3 - 6-pollicari ; capitulis e dichotomiis plerisque pedunculatis folia ful- 

 crantia adaequantibus ; acheniis intus prassertim parce pilosis, floris 

 centralis trigono apice truncato, radii obovato-oblongis trigono-ob- 

 compressis arcuatis, rostro brevi inflexo. (^Harpoecarpus madarioides, 

 Durand, PL Pratten. in Jour. Acad. Philad., non Nutt.) — Nevada 

 County, California, Mr. Henry Pratten. Washoe County, Nevada, 

 Mr. Stretch, communicated by Dr. Torrey. — Heads a line and a half 

 in length, larger than in the foregoing species. I think this was also 

 collected by Fremont, in his second expedition. But I possess no 

 specimen of it. 



WHITNEYA, Nov. Gen, Heleniearum v. Senecionearum, epapposum. 



Capitulum multiflorum, heterogamum ; floribus radii ligulatis foemi- 

 neis, disci tubulosis hermaphroditis. Involucrum biseriale, e squamis 

 10-12 ffiqualibus oblongo-lanceolatis acutis herbaceo-membranaceis. 

 Receptaculum convexo-conicum, epaleatum, dense hirsutum. Ligulaj 

 magnae. Corollge disci infundibuliformes, lobis breviusculis ovatis. 

 Antherae ecaudatae. Stylus radii elongatus, disci ramis brevibus linea- 

 ri-subulatis complanatis obtusiusculis extus hirtellis. Achenia oblonga, 

 obcompressa, calva. — Herba Arnicce facie, montium Californiae in- 



VOL. VI. 62 



