第 16 节
作者:无边的寒冷      更新:2021-02-20 04:47      字数:7669
  18 to   25   mm。   long   and   about   as   wide   at   base;   the   upper   surface   almost
  plane   and   smooth;   except   that   it   is   more   or   less   pulverulent   and   usually
  bears a small tomentose pulvillus (often evanescent later) just behind the
  claw…like   tip:   flowers   rose…color:   fruit   elongated…   oval   and   reddish。   (Ill。
  Lem。 Cact。 t。 1。)Type unknown。
  Referred to Mexico in general; but reported definitely only from San
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  Luis Potosi。Undoubtedly found in Coahuila; and possibly crosses the Rio
  Grande in the region of the 〃Great Bend。〃
  Specimens examined: San Luis   Potosi (Eschanzier of 1891): Mexico
  in   general   (specimens   from   Coll。   Salm…Dyck   in   1858;   Schott   of   1858):
  also specimens cultivated in Mo。 Bot。 Gard。 in 1881; also growing in same
  garden in 1893。
  3。 Anhalonium furfuraceum(Watson)。
  Mamillaria furfuraceaWatson; Proc。 Amer。 Acad。 xxv。 150 (1890)。
  Very closely related to prismaticum; but triangular portion of tubercle
  acuminate and shorter; having an irregularly mamillate upper surface; and
  the acumination ending abruptly in a cartilaginous depression containing a
  tomentose pulvillus: flowers 2。5 to 3 cm。 long; white or pinkish; the sepals
  brownish。 Type; Pringle 2580 in Gray Herb。
  At Carneros Pass; Coahuila。
  Specimens examined: Coahuila (Pringle 2580 of 1889)。
  The type of this species was not among the collections received from
  Cambridge;   but   a   specimen   of   the   same   distribution   from   the   National
  Herbarium shows tubercle dimensions different from those recorded in Dr。
  Watson's description。In that description   the triangular terminal surface   is
  said   to   be   〃about   an   inch   broad   by   one…half   inch;〃   which   is   decidedly
  different from the equilateral surface of the tubercle of prismaticum。In the
  National     Herbarium      specimen      of  furfuraceum;      however;    of   the  same
  distribution; the surface is almost equilateral; measuring 15 mm。 long by
  18 mm。 wide at base。Without the acuminate upper portion the breadth of
  the triangular portion would be about double its length。The lower rim of
  the   cup…like   depression   which   terminates   the   tubercle   and   contains   the
  pulvillus     is  sometimes       slightly   prolonged      into   a   tooth;   which     in
  prismaticum        becomes      the   sharp   tip   of   the   tubercle。The      〃minutely
  furfuraceous…punctulate〃   character   of   the   tubercle   is   common   to   all   the
  species   of   Anhalonium   I   have   seen;   and   simply   represents   the   external
  openings of the remarkably long cuticular passageways to the stomata。
  4。 Anhalonium pulvilligerumLem。 Cact。 (1839)。
  Anhalonium elongatumSalm…Dyck (1850)。
  This   seems   to   be   a   third   grooveless   Mexican   species。I   have   seen   no
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  specimens;   but   judge   from   the   description   that   it   differs   from   the   two
  preceding species chiefly in its less crowded and more elongated tubercles
  (triangular    portion    5  cm。   long   by  2。5   cm。   broad   at  base);  which    are
  covered at apex with a tomentose pulvillus。
  GEOGRAPHICAL
  DISTRIBUTION。
  This    curious   genus    is  strictly  Mexican;    and;   so  far  as  at  present
  recorded; is characteristic of Coahuila; but a single species (engelmanni)
  of the four or five known crossing the Rio Grande in the Great Bend。
  3。 LOPHOPHORA;gen。 nov。
  Depressed…globose;         proliferous    and    cespitose;    tuberculate…ribbed;
  unarmed plants: tubercles at first conical and bearing at summit a flower…
  bearing   areola   with   a   dense   tuft   or   short   pencil   of   compact   erect   hairs;
  when     mature    becoming      broad   and   rounded    (with   the   remnant    of  the
  penicellate tuft as a persistent pulvillus in a small central depression) and
  coalescing into broad convex vertical ribs: spine bearing areolae obsolete:
  flowers borne at the summit of nascent tubercles: ovary naked (that is free
  from scales; but often downy): fruit and seed unknown。
  These     forms    have    been    variously    referred    to  Anhalonium        and
  Echinocactus;   but   seem   to   deserve   generic   distinction。They   differ   from
  Anhalonium   in   the   entire   suppression   of   the   upper   highly   differentiated
  portion of the tubercle; in the broad and rounded development of the lower
  portion;    and   in  the   coalescence     of  the  enlarged    tubercles    into  broad
  vertical ribs。In fact; in young specimens; the plant appears almost smooth;
  with shallow furrows radiating from the depressed apex。The genus differs
  from Echinocactus in the suppression of the spine…bearing areolae; and the
  naked   ovary。In   the   examination   of   developing   tubercles   the   relation   to
  Anhalonium is evident。In the latter genus the young tubercle bears on the
  summit   of   its pedicel…like  lower portion   the tufted   flower…bearing   areola
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  the modified upper portion of the tubercle at that time appearing as a bract
  beneath   the   flower。In   Lophophora  there   is   the  same   condition   of   things;
  except that the bract…like upper portion is wanting。From this point of view
  it    would     appear     that    the    differences     between      Lophophora        and
  Echinocactus are intensified by the fact that the flower…bearing areola in
  the former genus is to be regarded as really lateral on a tubercle the upper
  part    of    which     has    disappeared。This       genus     occurs     abundantly      in
  southeastern Texas; extending southward into Mexico。Mrs。 A。 B。 Nickels
  reports   that   the   Indians   use   the   plants   in   manufacturing   an   intoxicating
  drink;  also   for   〃breaking   fevers;〃   and   that the   tops   cut off   and dried   are
  called 〃mescal buttons。〃
  1。 Lophophora williamsii(Lem)。
  Echinocactus        williamsiiLem。       Allg。   Gart。    Zeit。   xiii。  385    (1845)。
  Anhalonium williamsiiLem。 in Forst Handb。 Cact。 i。 233 (1846)。
  Hemispherical;       from    a  very    thick   root;  often   densely    proliferous;
  transversely lined below by the remains of withered tubercles: ribs usually
  8 (in young specimens often 6); very broad; gradually merging above into
  the distinct nascent tubercles which are crowned with somewhat delicate
  penicellate tufts; which become rather inconspicuous pulvilli on the ribs:
  flowers   small;   whitish   to   rose:   stigmas   4。(Ill。   Bot。   Mag。   t。   4296)Type
  unknown。
  Along   the   Lower   Rio   Grande;   Texas;   and   extending   southward   into
  San Luis Potosi and southern Mexico。
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