1916.] 



JEPSON : REGENERATION IN MANZANITA 



and, so far as observed, reproduces entirely by seed. Mr. W. C. 

 Mathews, one of my students, who has also observed it on the coast 

 region of Mendocino, has given me the results of identical observa- 

 tions on this species. Arctostaphylos glandulosa, on the other hand, 

 as noted above, flourishes under fire, and establishes heavy sub- 

 hypogeous platforms from which sprouts freely rise after fire. 



Fig. 2. 



Arctostaphylos nummularia is another coast species. (Fig. 3.) 

 It is very erect, with the branchlets crowded with small round 

 leaves. While locally abundant, and even gregarious (Fig. 4), it is 

 in general a rather rare species, and my observation of its behavior 

 on Mt. Tamalpais shows it to be killed Outright by fire. (PL II, B.) 

 One of my former students, Miss C. M. Hoak, makes a similar ob- 

 servation for the Mendocino White Plains. It may be that the re- 

 stricted occurrence of this species is due to its inability to respond 

 vegetativery from the root after chaparral fires, a fact which may 

 perhaps be connected with the character of its root-system, which is 

 spread out near the surface of the ground like an inverted umbrella. 

 In any event, the roots lie so near the surface of the ground that 

 they must suffer directly from the heat of chaparral fires (Fig. 5.) 



Arctostaphylos stanfordiana is a species of the Mt. St. Helena 

 range. It is remarkable for its deep-green glabrous leaves, and 

 clean, trim habit, and is susceptible of field recognition in this way 

 by those who notice manzanitas. This species, according to the avail- 

 able evidence, does not reproduce vegetatively. This testimony I 

 had first from Mr. Carl Purdy, who lives in its region, and Miss 



