OREOCEREUS CELSIANUS 
These noble plants are native to southern Peru, 
and northern Chile at elevations of 6000’ to 12,000’. | took 
this photograph in November, 1951, near Tarata, Peru before 
} The plants are extremely 
variable ranging from hairless to hairy and white to red- 
the advent of the rainy season. 
dish, 2’ to 8’ tall. The lady is Mrs. Johnson. 
OUR PERUVIAN EXPEDITION 
One of the most interesting facets of the 
study of plants is to speculate on how plants 
arrived where we now find them. However, 
first we must know something about their 
distribution. Not very much was known of 
the cacti of the Andean region of South 
America. The principal object of our wan- 
derings was to record the localities where the 
plants were growing and thus to learn the 
extent of distribution of each group or genus. 
With this knowledge one can be more certain 
of relationship between the groups and, by 
extension, more clearly see from what reser- 
voirs they overflowed. 
In September, 1951, | had my affairs suf- 
ficiently forward to take off for Ecuador 
where | intended to do further collecting in 
the jungle lowlands. Arriving at Quito my 
very good friend Dr. Acosta Solis kindly lent 
me the services of his best collector and we 
proceeded down to Puyo on the Rio Pastaza 
where with the aid of a Jivaro chieftain we 
secured many Marantas, Anthuriums, etc. 
Afterward we journeyed down to Quininde on 
the western flanks and found some _ lovely 
things. 
In October | flew to Lima, Peru, where my 
old friend Dr. Cesare Vargas C. of Cuzco 
was awaiting to accompany me on an odyssey 
to the north. We collected many interesting 
cacti about Huaraz a valley near the base of 
stupendous Mt. Hauscaran, its snowcapped 
peak reaching into the piled cumulus clouds 
22,000’. Two new Matucanas, a snowy Es- 
postoa, Milas, Armatocereus, several Borzicac- 
tus, Melocactus, Trichocereus, a new Oroya, two 
new Tephrocactus, one with snow white hair 
and scarlet blossoms were found. Leaving we 
crossed the Paso Callan at 14.000’ dropping 
down the brushy slopes to 4,000’ where a 
splendid white Pseudoespostoa grew to 8’ 
or more. Mila, Melocactus, Haageocereus and 
Neoraimondia were plentiful. Before reaching 
Trujillo a mew  WHaageocereus was found. 
Leaving our collections to the good care of 
our friends at the University we continued 
north, climbing to Cajamarca. Along the way 
a new Pseudoespostoa, slender and _ divari- 
cately branched, was collected together with 
a lovely golden spined Haageocereus, new 
Monvillea, Armatocereus, Neoraimondia and 
Melocactus. From Cajamarca we crossed to 
Celendin above the Rio Maranon. Leaving 
Cajamarca we found a curious Arequipa-like 
cactus near Arequipa myriacantha. Crossing 
the northern pass we climbed for hours over 
the bleak puna finally reaching San Miguel. 
A. splendid Borzicactus with 31’ spines 
clambered on the rocks at about 8,000’, a 
new Erdisia, new Echeveria and Opuntia were 
found. Below San Miguel were some lovely 
flowering shrubs one with exquisite, deep blue, 
Nicotiana-like pendent blossoms, a_ shrubby 
Eugenia with red blossoms and shiny leaves 
and a climbing Bauhinia with large trusses of 
pink blossoms. We came upon a _ stately 
golden cereus with a stout trunk and up to 
30 tall, slender branches each bearing a brown, 
wooly pseudocephalium. A_ glorious plant! 
Borzicactus plagiostoma grew with it. Lower 
grew Gymnanthocereus microspermus, a new 
Monvillea, two Armatocereus and Pseudo- 
espostoa. From Chiclayo we proceeded east to 
the Amazon crossing the continental divide 
at Abre Porcula, the lowest Andean pass, at 
INDEX 
Acanthocalycium _.. 17 Epiphyllanthus  ..___. 13 Neoporteria _..___ 18 
Adromischus _....... 5-6 Epiphyllum -.... 7-8-13  Notocactus ... 16-7-20 
Agave’ Sian. 3‘ Eriocereus _............. 15 Opuntia _........ 16-8-9 
Aloeveestt ea at 4 Erythrorhipsalis _.... 13 Pachycereus 16 
Escobaria _.........._... 16 
Aporocactus __...._.. 16 Espostoa ___.. 13-14  Pachyphytum _...... 7 
Argyroderma .......... 6 Euphorbia __........ 4-6 Pachyveria ............ 6 
Arthrocereus 14 Faucaria  2.......o..-..= 6 Parodia noe 17-20 
Ariocarpus ___.. 18-20 Fenestraria 7 Pelargonium 3 
Astrophytum 13-6-8-9 Ferocactus ............ 19 Pelecyphora _......... 18 
Azureocereus ___.. 15 Gasteria  __............:. 3 Pereskia  __..........__.. 15 
Cereus 32 19-20 Gibbaeum ____...... 7, Piaranthus § __......_... 7 
Ceropegia _._...........-. 6 Gymnocalycium Pleiospilos -........... 4-5 
Cephalocereus T4s9o58 ee ee 14-5-6-7 Pseudoespostoa ___.. 18 
Chamaecereus __..... 20 Hamatocactus __.. 16 Psuedorhipsalis 13 
Chiapasias 13 Hatioraye 2 ees 13 Pyrrhocactus _-____. 18 
Cleistocactus 14-5-6 Haworthia ___. 3-5-6-7 Rebutia ____......-. 16-7 
Cochemeia _....... 16 Hoya Pee eae ee 4 Rhipsalis ___........-..- 13 
Conophytum ...... 5-6 Hylocereus ___...... 13 Rochea) 2.)22) 8223 5 
Coryphantha _._. 16 Islayao ee 16 Sedum _____.......... 6-7 
Crassula _____.. 3-4-5-6 Jatropha’ .......-2-.--.- 6 Selenicereus 13-9-20 
Dinteranthus _......... 7 Kalanchoe .............. 7 Solisia, = Se 18 
Disocactus  —........... 13 Kleinia 22333 4 Stanelia:: 5-6 
Dolichothele —__...__.- 16 Lapidaria ___............ 7 Stenocactus ___.... 14 
Echeveria _........ 3-4-5 Lemaireocereus —__... 18 Tephrocactus ... 20 
Bolivia Echinocactus 18-20 Leuchtenbergia ___. 14 Titanopsis _._...... 7 
Echinocereus ___.. 13-9 Lithops:.c¢2)- 5 Tradescantia 7 
Echinomastus 14 Lobivia 14-5 Weberocereus __.... 13 
Echinopsis 14-5-7 Mamillaria Weingartia _....... 14 
Edithcolea  _.______.. 3 f° ee 4-5-6-7-8-9 Werkleocereus —_. 13 
Milas eee Zygocactus _._____. 13 
cephalium of shining white bristles. Three 
AZUREOCEREUS NOBILIS 
2000 meters. On the west side were many 
cacti, Neoraimondia, Armatocereus, Haageo- 
cereus} Gymnanthocereus microspermus and 
G. species, Rhipsalis, Hylocereus, Espostoa mo- 
cupensis, Pseudoespostoa, Trichocereus, Mon- 
villea also a lovely pink Bougainvillea. At the 
top on the east was a bright so'lden spined 
Seticereus. Lower grew Espostoa lanata in 
abundance all the way to the Amazon, both 
red and white spined. A fine new Gymnan- 
thocereus, a curious prostrate Borzicactus, and 
two new Armatocereus were collected. Below 
Pucura was a huge trunked Acanthocereus, 
two new Monvilleas, a strange red flowered, 
whip stemmed cereus, a new genus of colum- 
nar cacti with large white nocturnal flowers 
and a new genus of tree cacti with spineless 
branches and curious, nocturnal, scarious scaled 
flowers. Two odd, shrubby Pereskias and quan- 
tities of a fine new Melocactus were about. 
Thrixanthocereus grew to 15’ with pseudo- 
cephalia 10’ long. Espostoa reached enormous 
size, 20’ tall with 27’ spread and also it 
crossed to the east side of the Maranon. 
Back at Lima we shipped our collections 
home. My wife joined me here and we pro- 
ceeded up through Anticona Pass 15,800’ to 
Oroya and Huancayo and thence some 500 
miles south-east to Lake Titicaca. This is a 
spectacular but little known region between 
the eastern and western cordilleras where 
one climbs to 14,500’ travelling slowly through 
the cold, still mists and then drops precipi- 
tously into the vast, hot river valleys, over 
and over again. We collected many new 
cacti of great interest. Between Mejorado and 
Abancay were our splendid new Azureo- 
cereus one, the handsomest cactus | know, 
a tall bright blue column crowned with a 
2 
new Cleistocactus, a new cereus near Tricho- 
cereus up to 20’ tall, new Erdisias, Lobivias 
and Corryocactus, Morawetzia, Oroyas by the 
million and never ending variations of Teph- 
rocactus floccosa. Here also were lovely Be- 
gonias, Fuchsias and many Amaryllads. Reach- 
ing Cuzco | went to the lowlands following 
the Rio Urubamba below Macchu Picchu to 
Quelluno. There Cereus vargasiana grew to 
50’ with Rhipsalis, Epiphyllum, Trichocereus, 
Erdisia etc. Near Cuzco were many Lobivias 
and Erdisias some quite new. Driving on to 
Puno, finding Lobivias, then around the lake 
to lIlave leaving the cold, dark waters of 
Titicaca near the Bolivian border turning west 
to cross the highest Andean pass at 16,200’ 
encountering Tephrocactus ignescens at 15,000/ 
This is a very dry region. There were thou- 
sands of alpacas grazing and small herds of 
the graceful vicunas. On the west side the 
mountains toward Bolivia and Chile were 
brilliantly colored in rust reds, purple and 
yellow, a wild, tumultuous concourse of barren 
peaks and ranges. As we descended we found 
Corryocactus at about 12,000’ and then our 
first Oreocereus. They were plentiful in every 
conceivable variation to about 6,000’. Below 
Tarata we found two or three new Arequipas, 
Opuntias, Corryocactus, Armatocereus, Tricho- 
cereus, Tephrocactus and a new genus linking 
Cleistocactus and Oreocereus. Below grew 
Browningia candelaris and a curious procum- 
bent cereus near Arequipa. Arriving at Tacna 
we had a chance to rest and prepare speci- 
mens. 
From Tacna to Moquegua we traversed the 
rolling, barren, red pampas with a diversion to 
the sea through a lifeless sand drowned 
range to the port of Ilo. Haageocereus, 
Tephrocactus and Islaya grew sparsely. North 
of Moquegua in the fog belt was .a wealth 
of new things. Creeping Haageocereus, new 
Pygmaeocereus, new Corryocactus, Armato- 
cereus, a fine procumbent new Trichocereus 
and a new Borzicactus-like prostrate cereus. 
At Arequipa we rested then crossed to the 
Valle de Majes and to Chuquibamba finding 
more Haageocereus, Corryocactus, Trichocereus, 
etc. Above Camana we collected a lovely new 
Islaya with red flowers, another Pygmaeo- 
cereus, another Borzicactus-like cereus also 
a brilliant Portulacad, manv lovely annuals, 
alstroemeria and bulbs. Haageocereus and 
Islayas were found north to Atico. Near Atico 
were Haageocereus, a large new Islaya, Corry- 
oecactus and Neoraimondia and the wild parent 
of the garden Nasturtium. At Chala we went 
inland to 14,000’ finding several new Teovhro- 
cactus, Arequipa, Corryocactus, Neoraimondia, 
a new Browningia, Trichocereus, Matucana, 
Pygmaeocereus, Haageocereus, Islaya, Maritin- 
ocereus and a handsome new columnar, red 
flowered cereus. From Nazca we climbed 
to Puquio finding another red flowered cereus 
a handsome, white wooly Trichocereus, Arma- 
tocereus, Browningia, Haageocereus, a new 
Erdisia and a handsome new species of Oreo- 
cereus. North from Nazca we stopped at Ica 
staying at thea strange dune rimmed Jake of 
Huacachina. Arriving in Lima we packed our 
collections and returned to Ecuador and Co- 
lombia. On our way home a short stay in 
Nicaragua and Guatemala brought us several 
more interesting plants including Lemaireo- 
cereus aragonii. 
