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Demography of the rare perennial herb Santa Ynez thermopsis (Thermopsis macrophylla var. agnina) was monitored at two sites for 9 yr after a controlled burn in the Santa Ynez Mountains near Santa Barbara, California. One of the burned sites was located in chaparral and the other in a fuelbreak, an area purposely cleared of chaparral to slow the advance of wildfire. Numerous individuals resprouted in the 1st yr after the fire and thousands of seedlings established from heat-stimulated germination of refractory seed. Vegetation before and after the fire was markedly different between the two sites. Despite this difference, however, seedling production was very similar on the two sites. Losses of recruits-seedlings that survived beyond the 1st yr-also were similar. Nine yr after the fire the density of recruits was equivalent on both sites. Recruits were significantly taller in the fuelbreak than in the chaparral but the average number of stems/individual was not different. Individuals that resprouted after the fire produced more than 106 seeds/900 m2 from 1980-1987. However, only 3.9% of the seed was present in the soil 8 yr after the fire. Seed production by recruits, in contrast, was very low and appeared to be declining. Thus, this species relies heavily on seed production by resprouts to maintain a sizable soil-seed bank. In addition to seed production by resprouts, the survival of recruits during the interfire period is a critical life history stage in the population biology of this species. Recruits that survive both the interfire period and the next fire show marked increases in stem production, seed output and survivorship.

During a monographic treatment of the genus Baptisia, interest was aroused in the state of taxonomic confusion into which its closest generic affinity, Thermopsis, had fallen. According to the "Index Kewensis" and the Gray Herbarium Catalogue, it is comprised of thirty species: eight Asiatic, not considered in this revision; and twenty-two North Americanfour from the southeastern United States, and eighteen from the western United States. The latter group constitutes a western geographical supplement of Baptisia whose western limits roughly coincide with the eastern limits of Thermopsts. The problems were found to be largely bibliographical. The present treatment proposes no novelties, but has indicated two new combinations. It consists largely of a drastic reduction of a number of species. The four heretofore recognized southeastern species are reduced to three, and the eighteen western species have been reduced to seven species and five varieties. A key to the species, and brief descriptions with complete citations of synonyms and type or authentic specimens are given. Relative uniformity, particularly within the western group, makes delimitation of entities difficult in many cases. As in Baptisia, flower structure furnishes little of value in this respect, and has therefore been given little emphasis. Fruit and vegetative characters seem to be the best bases for the separation of species, and have been stressed accordingly. Considerable doubt is felt by the author as to the validity of the two varieties of T. rhombifolia: annulocarpa and arenosa, for they