2. The Chicama and nearby lomas. Despite the small number of collections, this region is distinctive in two features -- the endemic ecological conditions of the Cascas-Contumazá area and the only loma collections known for the species. 3. The Moche-Pisco region. Here three gaps can be detected in collections: one between the Moche and the Santa, another between the Casma and the Fortaleza, and the third between the Lurín and the Canete. The reasons for the gaps seem to be: (a) the rivers do not have enough moisture to  sustain  growth  at  the  altitude  preferred  by  the  species;  (b)  they  have  not  been  explored sufficiently in favorable years; and (c) the populations are usually very small. 4. The Marañon region. East of the Andean divide, only the Marañon River and its tributaries have yielded hirsutum  accessions.  We  have  arbitrarily  divided  the  collections  into  two  subgroups:  (a) the collections of the Huancabamba and Cajamarca Rivers, which are closely related to those of the  Piura  and  Jequetepeque  watersheds,  respectively;  and  (b)  specimens  from  tributaries  that flow directly into the Marañon. Identification of the latter group is of doubtful reliability because the locations are isolated and scattered and because no seed is available to permit the growing of test  cultures.  The  situation  should  be  cleared  up  by  a  collecting  expedition  into  this  highly complicated and poorly understood vegetational area. f. glabratum extends southward from Ecuador to Olmos (6o south latitude) in the Chira-Jequetepeque region and is found from 500 to 2700 m. The fruit seems to be available in the last part of winter and early  spring  (Aug.-Oct.),  and  plants  spread  along  hillsides  in  the  usual  quebrada  situations  in  the presence of abundant shrubby vegetation. In the Chancay-Jequetepeque area, conditions are drier, vegetation is sparse, and f. typicum starts to appear. b.  L.  chilense  (Table  2).  This  species  is  present  in  the  exceedingly  arid  region  of  southern  Perú  from Chaparra to Tacna and along the northern coast of Chile. Populations are tiny north of Moquegua, but  southward  they  tend  to  be  larger.  Seed  collections  were  made  in  the  November  through  April season which corresponds to the "rainy season" in  normal years. Since this period is too short for vegetative growth (from the perennial "stumps"), flowering, and seed production, the collection of a good seed supply in a given year indicated that sufficient moisture was received in the previous year. In fact, mature fruits have been collected two years after the last recorded rainfall. The altitude ranges can be roughly divided into three levels: (1) sea level to 1800 m; (2) 2200- 2500; and (3) 2800-3000. Good data for vegetation associations are not available; one good reason is that several sites have been described as extremely dry desert situations where very few other plants survive.  One  sympatry  reported  is  with  L.  peruvianum  in  lomas  of  Tambo  at  500  to  1300  m  and another with yellow-flowered Solanum lycopersicoides at Palca, Caplina watershed, 2500 m. The  sites  are  very  dry  and  stony  with  sandy  situations  in  washes  (quebradas)  for  half  of  the collections;  and  for  the  other  half,  they  are  roadsides  (500,  1000-1500,  and  2900  m)  or  hillsides (1000-1400, and 3000 m). c.  L.  peruvianum  (Table  3).  In  the  overall  analysis  of  collectors'  data,  this  species  is  divided  into  four geographic  categories:  (1)  the  loma  collections,  (2)  the  region  from  Ecuador  to  the  Reque-Chancay watersheds, (3) the coastal type and the "mountain races" from the Jequetepeque to the Nazca Rivers, and  (4)  the  area  of  peruvianum/chilense  sympatry  from  Rio  Lomas  to  northern  Chile.  These apparently  natural  divisions  are  based  mainly  on  the  data  reviewed  and  the  crossability  relations developed by Rick (1963; summary in his fig. 4). L. peruvianum has been collected since 1788 (Ruiz and Pavón, Rímac watershed) and is still found today in old and new sites. It is rare north of the Jequetepeque and has not been collected in such short  valleys  as  Virú,  Chao,  Nepeña,  and  in  a  gap  between  the  Pisco  and  Nazca  drainages.  In southern Perú it gradually disappears as L. chilense completely replaces it in the Moquegua, Sama, and  Caplina  watersheds.  In  northernmost  Chile  (Arica)  both  species  are  found;  southward  only  L. chilense has been reported.

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