Graptopetalum orpetii sp. nov.

Herba acaulis, omnino minutissime papulosa, foliis rosulatis carnosis cuneatis oblongis-oblanceolatis acuminatis cuspidatis, supra concaviusculis, dorso rocundatis, apicibus leviter incurvis 20-35 mm. longis; corollae-segmentis valde patulis, transverse-fasciatis, calycis-lobis turgidis corollae-tubo longioribus.

Gratopetalum is a genus of the Crassulaceae taking its name from the curiously marked petals, and is another of Dr. Rose's many segregates from Cotyledon, which last according to him is not represented in the new world. Until recently the former genus was thought to consist of only 4 species, but we here describe what is undoubt­edly a valid, new species, besides transferring the plant commonly known as Byrnesia weinbergii to what appears a more logical generic position. In regards to the latter, Rose himself hinted that it was close to Graptopetalum; and it is certainly difficult to maintain a monotypic genus on vege­tative characters alone. Other genera very similar in floral structure are Altamiranoa, Gormania and Stylophyllum. The whole question of generic delimitation in the Crassulaceae is still far from being finally settled, and A. Berger's treatment in the new edition of Engler & Prantl's "Natürliche Pflanzenfamilien" is awaited with curiosity.

Graptopetalum orpetii n. sp. (Habit-sketch of type; x 1.)

The plant on which the description of this new species is based was found by Mr. Ed. Howard of Santa Monica on the road to the Boyce-Thompson Arboretum at Superior, Arizona, in the spring of 1929. With the approval of the dis­coverer we name it after Mr. E. O. Orpet of Santa Barbara, as a small recognition of the latter's many services not only to Horticulture in general, but the cult of Succulents in particular. At this time the writer also wishes to acknowl­edge his indebtedness to Miss Alice Eastwood in granting access to the type of G. rusbyi, as well as for kindly reading proof; and to Mr. James West for gracefully resigning his interests in the matter and furnishing the accompanying photo­graphs.

The new species comes closest to G. rusbyi, but differs from the latter in its relatively longer and more pointed leaves which are distinctly concave above and upcurved towards the apex, in the less prominently marked corolla-segments and last, but not least, in the decidedly shorter corolla-tube. It also resembles G. pusillum, the type of the genus, at least in its foliage, but differs from that in its longer, blunter and much more turgid calyx-lobes, as well as the more gradually attenu­ate carpels, which latter are only slightly longer than the sepals at anthesis.

Fig. 1 Side-view of corolla (x 5);

Fig. 2 Side-view of carpels (x 5);

Fig. 3 Corolla, opened out, showing 3 segments with the attached stamens (x 5);

Fig. 4 A single leaf (x 2.1);

Fig. 5 Cross-section of leaf (x 1)

Graptopetalum orpetii, new species.

(Type collected in Arizona, on road to Boyce-Thompson Arboretum at Superior, Arizona, by E. Howard, 1929, deposited in herbarium of California Academy of Sciences, San Francisco, sheet No. 170322. Description from living plant growing in greenhouse of V. Reiter, Jr., San Francisco. Photo by James West. Drawings by the author.)

Plant acaulescent, cespitose, rosettes to 7 cm. in diameter, each with as many as 25 leaves;

Leaves oblong-oblanceolate, cuspidately-acuminate, cuneate towards base, 20 to 35 mm. long and 6 to 10 mm. broad above middle, courge-green (*3) below, light elm-green (*4) above, glabrous, finely punctate with many elongate papillae in close longitudinal rows, strongly convex below, shallowly concave above, slightly upcurved towards the end;

Inflorescence of several lateral, simple or cymosely branched scapes 6 to 9 cm. tall;

Peduncle 2 to 3 mm. thick;

Bracts scattered, linear or nearly so, caducuous;

Branches 2 to 3, ascending-spreading, secund racemes each with 4 to 7 flowers;

Pedicels 3 to 5 mm. long, about 1 mm. thick;

Flowers erect, mostly 5-parted;

Calyx-lobes turgid, 5 to 7mm. long, appressed to corolla, oblong, obtusish, finely mucronate, punctate and colored as the leaves, but often with some pigmented papillae towards apex, longer than co­rolla-tube;

Corolla conspicuously pentagonal in bud, to 14 mm. in diam. when open;

Segments spreading radially, keeled on back, chanelled on face, narrowly-deltoid to lanceolate, acuminate, about 8 mm. long by 2 mm. wide at base, united for about one-third to one-fourth their length, ground-color light chalcedony yellow (*4), but at apex with relatively few transverse bands or markings of eugenia-red (*4), the dark coloration being due to the colored cell-sap of certain groups of epidermal papillae, and possibly more marked in plants growing in their na­tive habitat;

Corolla-tube distinctly shorter than the calyx-lobes;

Stamens 10, attached to corolla-tube near its upper end, not merely adnate to the lat­ter, at first erect, widely spreading after pollen is shed, and even becoming reflexed when stigmas are receptive, short­er than the petals;

Anthers brownish, quadratic in outline;

Carpels white, slightly longer than sepals, short­er than stamens, gradually attenuate into styles;

Stigmas at first indistinct, later papillose and greenish when receptive;

Hypogynous scales transverse, lunate-reniform;

Fruit as yet unknown.

Editor's Note: Mr. Walther, 2667 McAllister St., San

Francisco, would be glad to receive communications from

any one desiring to make any comments.

Fig. 6 A single leaf (x 2.5)

Fig. 7 Cross-section of leaf (x 2.5)

Fig. 8 Habit sketch, from living plant collected by Miss Alice Eastwood on Apache trail, Arizona, May, 1929 (x 1)


(*3) French for some kind of squash; see footnote *4.

(*4) Color-nomenclature after Ridgway.

© Cactus & Succulent Journal of America, 1930