300 CALIFORNIA ACADEMY OF SCIENCES. 



53. Ambrosia. 



This is either a new species or a variety of A. artemi- 

 sicefolia. It is too young for satisfactory determination. 

 The plant collected is annual, 9 dm. high, branching; the 

 sterile heads have pedicels 2 cm. or less in length; the 

 5-lobed involucres are open-campanulate, 5 mm. in diam., 

 and surpass the staminate flowers; the pistillate flower 

 has a beak a little over 1 mm. in length. 



Collected in Willow Creek Canon where it seemed 

 rare; seen in no other place. 



54. Franseria Hookeriana Nutt., Trans. Am. Phila. 

 Soc, N. S., vii, 345 (1841). First described as Am- 

 brosia acanthocarpa Hook., Flor. Bor. Am., i, 309. 



Type locality: "Near the sources of the Colorado of 

 the West." 



Two forms of this variable species were collected in 

 the same locality differing considerably' from each other. 

 Not having access to the types of this polymorphous spe- 

 cies I cannot tell which form is nearest, so it seems best 

 to describe both. 



55. Annual, erect and simple up to the inflorescence; 

 scabro - hispidulous; lower leaves bipinnatifid with 

 broadly -ovate circumscription, divisions lobed; upper 



10-15 mm. long, 10 mm. broad, membranous, intricately veined, present- 

 ing an irregularly pitted surface, glandular-hairy; akene oblong, beaked at 

 the truncate apex by the base of the style, mottled with brown, with scat- 

 tered hairs and yellow glands; pectinate margin inclined to be scarious; 

 male flowers in staminate heads twice as long as the bracts of the invol- 

 ucre; upper leaves spatulate. It is allied to Dicoria canescens, but has 

 much larger bracts covering the akenes, the toothed edge to the akene is 

 narrower and less scarious and the upper leaves not orbicular. 



While I believe it a bad plan to describe plants from such poor material, 

 yet as the essential features were all represented in the scraps it seemed 

 better to call attention to this new member of a genus represented by so. 

 few species. 



Type in the Herbarium of the California Academy of Sciences. 



