US THE CACTACHAIC. 



3. Heliocereus speciosus (Cavanilles) Britton and Rose, Contr. U. S. Nat. Herb. 12: 434. 1909. 



Cactin .\/>c. /c.uf.s Cavanilles, Anal. Cienc. Nat. Madrid 6: 3.19. 1X03. 



Cinlm speciosissimus Desfontaines, Mem. Mus. Hist. Nat. Paris 3: 193. 1817. 



('i-n-iis liifrons Haworth, Snppl. I'l. Succ. 76. 1819. 



('rir;i>. .i/HTiHsixsimiis DC Candollc, Prodr. 3:468. 1828. 



( V/CHS s/>r< /n.wi.s Sc-liumann in Englcr and Prantl, Pflanzenfani. 3 i; rl : 179. 1X94. Not Sweet, 1826. 



Stems clambering orjianging, strongly 3 to 5-ribbcd, old parts bright green, young parts 

 i eddish; ribs strongly undulate; areoles distant, often 3 cm. apart, usually large, with felt and 

 acicular spines; spines numerous, yellow or brownish in age, r to 1.5 cm. long; flowers scarlet, 15 

 to 17 cm. long, lasting for several days; perianth-segments oblong, 10 to 12 cm. long, with rounded, 

 often apiculatc tips; filaments weak, red; style little longer than the stamens; stigma-lobes white; 

 ovary bearing scattered minute scales; fruit ovoid, 4 to 5 cm. long. 



Type locality: Described from a garden plant. 



Distribution: Central Mexico and reported from Central America. 



Dr. Rose found this species very common on the pedregal near the City of Mexico. It 

 there forms large masses, usually growing in the pot holes and at the mouths of dark caves, 

 clambering over the rocks and occasionally giving off roots. Mr. Pringle found it at high 

 elevations on the mountain ranges south of the City of Mexico. 



Ccreus speciosissimus grandiflorus (Pfeiffer, Enum. Cact. 122. 1837) is a hybrid with 

 Sclcu iccrcus grandiflorus. 



Cereus speciosissimus hausii Baumann (Forster, Handb. Cact. ed. 2. 773. 1885; C. 

 haiisii Haage in Forster, Handb. Cact. 428. 1846) is a hybrid with Epiphyllum ackermannii. 

 Cereus jcukiusoni (Sweet, Hort. Brit. ed. 2. 237. 1830; C. speciosissimus jctikinsouii 

 Pfeiffer, Enum. Cact. 121. 1837) is a hybrid obtained in 1824. Ccreus jenkinsonii verus 

 Haage (Forster, Handb. Cact. 429. 1846) is another hybrid. Here also belongs Ccrctts 

 speciosissimus lateritius Pfeiffer (Enum. Cact. 121. 1837), which was earlier described and 

 figured as Cactus speciosissimus lateritius (Edwards's Bot. Reg. 19: pi. 1596. 1833) and, 

 afterwards, as Cereus lateritius Salm-Dyck (Cact. Hort. Dyck. 1849. 53. 1850). The 

 variety of Cereus speciosissimus, albiflorus (Cereus albiflorus Schumann, Gesamtb. Kakteen 

 Nachtr. 54. 1903), though first mentioned in 1837, was without description, but was taken 

 up and described along with coccincus, Iwvcyi, and peacocki by Riimpler (Forster, Handb. 

 Cact. ed. 2. 772, 773) in 1885. 



Cereus speciosissimus aurantiacns (Pfeiffer, Enum. Cact. 122. 1837; C. aurantiacus 

 Forster, Handb. Cact. 428. 1846) is very briefly described. 



The following are some of the hybrids of Ccreus speciosissimus with Epiphyllum phyl- 

 lantlioides which are listed by Walpers (Repert. Bot. 2: 278. 1843): bodii, bollv.'illcrianus, 

 bi'n'lrianiis, ciiriisii, ciigciiici, guillardieri, ignescens, kiardii, longipes, lotliii, iiiaclcnii, ui-:\i- 

 cuiius Salm-Dyck, nndii, sarniensis, superbus, unduliflorus, vandesii, ritelliuus, and 

 suwaroffii. Some of these names had been previously used by Pfeiffer (Enum. Cact. 121. 

 1837) as varieties of this species, as follows: var. cnrtisii, eugenia, guillardieri, ignescens, 

 kiardii, lotliii, and roydii. 



Among other named hybrids, Pfeiffer gave var. devauxii (Cereus devauxii Forster, 

 Handb. Cact. 428. 1846). Forster (Handb. Cact. 428 to 431. 1846) also mentioned 66 

 hybrids with this species, among which are: blindii Haage, colmariensis Haage, daniclsii 

 Haage, cdcsii Booth, clcgans Booth, finkii Salm-Dyck, gebvillerianus Haage, gloriosus Haage, 

 hitchensii and its varieties hvlvidiis and speciosus, kampinauuii Haage, kobii, latifrons, 

 loudonii, iiiacqitcaiius vSalm-Dyck, maurantianus, merckii Booth, mittleri vSalm-Dyck, 

 muhlhausianus, pcintncri Haage, rintzii Salm-Dyck and the two varieties roscns albus and 

 roseus supcrhus, seitlelii Booth, scitzii, selloii, siuithii (Epipliylluin sinilliianuin Marnock, 

 1'loricult. Mag. 8: pi. 13), suwarowii, and iriumphans. In addition to these there are 

 many hybrids with only an English name. There are also many quadrinomials. 



