AUi^llsl 31, I'M I ''/ 



C. INTI-H^KA (»ra\-, Hot. Me\. I'.oiind. 119. 1S59. 



Dislrihuted from Colorado to Arizona, Cliiluiahna, vSonora, 

 and western Texas. Among its earliest collectors were Wright 

 and Higelow. Collected in the Rincon mountains on a north 

 slope at about 7500 feet, October 3, 1907, no. ^,vy>, and also in 

 an upward extension of the Transition zone in the Santa Cata- 

 linas, at Sooo feet, July 7, 1910, no. 3212, and a few hundred 

 feet lower, June 16, 1910, no. Jji 2. Near Paradise in the Cliir- 

 icahuas it was found October 17, 1907, no. 2242, and October 

 22, 1907, no. 2 2 JO, the latter at 6000 feet, the former on lime- 

 stone at 6500 feet. One lone flower was gathered in the saiue 

 mountains October 22, 1906, at Rhoda Rigg's ranch, no. iSgj, 

 at as low an altitude as 5500 feet, but it was hidden among 

 shrubs along the creek. Al.so referred here is no. 2S00 from the 

 Pesquira hills near Arivaca, in southeastern Arizona, collected 

 March 30, 1909, by Mi.ss Eva Sine, ''high up among rocks on a 

 mountain side." Unless this was a north slope, it may prove to 

 be distinct from C. hilegra^ as the altitude was only 3500 to 

 4000 feet. 



In the Rincons C. integra is a species of the Transition 

 zone, and forms a connecting link between C. laxa of the Upper 

 Sonoran zone below, and C. aiLslroinontana of the Canadian 

 zone above. The species occurs as single stemmed or few 

 stemmed plants onl\', not in many stemmed clusters as does C. 

 laxa here. P'roni C. austronioiitana it differs in its more scat- 

 tered occurrence. Bv its structure and velvety appearance, it is 

 very disnncl from either. All three here grew upon essentially 

 the same kind of soil, derived from schistose granite or mica 

 schist. At ])laces where the contact of the Transition and Can- 

 adian zone is well marked by major species, C. integra and C. 

 austyomoiitaiia also meet, but do not ox'erlap, and each species 

 thus characterizes its own zone. Whether the same is true 

 where C. iulrgra and C. laxa come in contact is not yet clear, 

 as opporiuniiN to examine this point did not present itself. 



In ascending the vSanta Catalina range from Oracle, the 

 three species were found succeeding one another in the same 



