A. LENTIFORMIS. 337 



5. A. ORBiCDLAHis Watson, 1. c, 17:377, 1882. — The monoecious state of A. lenliformis breweri, "the 

 small dense staminate clusters with the pistillate flowers and in slender terminal moniliform spikes." Watson 

 did not compare his proposed species with any member of the lenliformis group, but Parish, the collector of 

 the type specimen, has reduced it to breweri, and has given ample reason for so doing (Erythea 7: 91, 1899). 

 Still later studies along the coast of southern California, especially in Ventura County, confirm Parish's con- 

 clusion. Nearly all stages in the separation of the sexes are foimd. Some plants are about equally male and 

 female, others in the same environment and not distinguishable by other characters vary to purely pistillate 

 and to purely staminate. Very few plants of either sex fail to reveal at least a few flowers of the other sort 

 on careful examination. Santa Monica is the type locality for both breweri and orbicularis. 



6. A. TOURETi Watson, 1. c, 9: 119, 1874. — A. lenliformis lorreyi. 



7. OmoNE i.ENTiFORMis Torrey, in Sitgreaves, Rep. Exp. 169, 1853. — A. lentiformis typica. 



8. O. TOHUEYi Watson, Bot. King's Expl. 290, 1871. — A. lentiformis lorreyi. 



RELATIONSHIPS. 



When taken in the extended sense here adopted, Atriplex lentiformis is well set off 

 from all other species. The compressed orbicular fruiting bracts suggest a relationship 

 with A. hymenelytra, while the very woody and subspinose habit suggests connections 

 with A. confertifolia. It is more primitive than either of these in the retention of a 

 strong tendency toward monoecism in subspecies breweri and typica. 



The four subspecies are geographic as well as morphologic, as has been mentioned 

 in the paragraph introductory to the key, but only subspecies griffithsi is truly isolated, 

 the ranges of the others meeting along their borders. Subspecies typica and breweri 

 are the most difficult to distinguish. The best mark of the former is the crenulation of 

 its fruiting bracts. But plants with entire bracts are sometimes found well within the 

 area of typica and with the other features of this form (Bakersfield, California, September 

 24, 1894, Eastwood, Gr, UC; Kern Lake, Davy 2911, UC). The crenulations are never 

 very pronounced in typica, which was originally described by Torrey as "bracteis 

 orbicularis integris vel remote repando denticulatis," and the bracts of breweri commonly 

 are at least undulate. The degree of compression of the bracts also has been used as 

 a distinguishing character, but without much success. The impressions made upon 

 different botanists is indicated by the fact that, although Standley (N. Am. Fl. 21: 

 63-64, 1916) describes the bracts of breweri as strongly convex and those of typical 

 lentiformis as strongly compressed, Parish (Erythea 7:91, 1899) and Jepson (Fl. Calif. 

 440, 1914) could see no difference between breweri and orbicularis, the bracts of the latter 

 also described by Standley as strongly compressed. Field studies indicate that the 

 bracts of breweri have a tendency to be thicker than those of typica. This is perhaps 

 the effect of the maritime habitat of the former. The leaves and bracts average larger 

 in breweri, as would be expected in a seacoast form, and this may in turn account for the 

 smoothing out of the margins. Monoecism is common in breweri, but not wanting in 

 typica, for in the San Joaquin Valley, California, where this subspecies abounds and 

 where dioecism is the rule, entire branches loaded with fruiting bracts may be found on 

 plants otherwise staminate, while on other plants the sexes are about equally represented, 

 the two kinds mixing in the inflorescences. Specimens illustrating these intergradations 

 in various characters are on file in the herbarium of the University of California. 



Subspecies typica is met along the easterly part of its range by subspecies lorreyi. 

 It is not known that they actually intermingle, although they have been reported from 

 the same locality. The latter form is more inclined to be spinescent, in keeping with its 

 more arid habitat, but its distinguishing feature is the development of sharp longitudinal 

 ridges on the twigs. No exact intermediates in this respect are known, but in a specimen 

 of typica from Tempe, Arizona (September 4, 1901, Thornber, UC) the branches of the 

 staminate inflorescence are decidedly angular, approaching in appearance those of 

 torreyi. Subspecies griffithsi is a little-known form of southeastern Arizona, remarkable 

 for its narrow leaves and relatively broad fruiting bracts. 



