2. Taxodium mucronatum Ten. Montezuma bald cypress, sabino, ahuehuete, 

 ciPRES. Fig. 23. 

 Large tree with straight trunk enlarged near the base, to 30 m. high; bark 

 brownish-red, relatively smooth to shallowly furrowed, fibrous, more or less 

 shredded; leaves linear, 6-12 mm. long, spreading in nearly 2-ranked sprays, these 

 and some young branchlets falling with appearance of new growth; staminate 

 cones small, ovoid, 1.5-2.5 mm. long, in slender spikes 5-15 cm. long; ovulate 

 cones subglobose, 15-25 mm. in diameter; seeds dark-reddish-brown, 4-8 mm. 

 long, irregularly angular because of crowding. 



Along the Rio Grande and occasionally along resacas in Cameron and Hidalgo 

 cos. in the Rio Grande Valley of Tex.; from s. Tex., s. on the Mex. tableland 

 and along the coast of the Gulf of Mex. 



This species is the famous large tree of Santa Maria del Tule, Oaxaca, Mexico, 

 which, according to the best authority, has a height of about 39 meters and a 

 trunk circumference of 52 meters, with the spread of its branches about 42 

 meters. 



Class 2. Angiospermae 



Plants diverse in habit, structure, form, size, habitat and sexualization; ovules 

 and seeds borne enclosed in carpels that are at the center of flowers and which 

 are interpreted as fertile fronds with megasporangia on the upper surfaces, these 

 fronds are loosely folded along a median zone in such a way that the margins 

 meet to form a more or less firmly sealed ventral (adaxial) suture; carpels either 

 free (constituting a simple pistil) or often several united into a compound pistil; 

 ovule-bearing portion of the pistil (the ovary) maturing into the fruit; gameto- 

 phytic stage of the plant of very short duration (a matter of only a few hours) 

 as compared to the gymnospermous counterparts, and the male gamete reaching 

 the female gamete (in the ovule) by means of a tube that penetrates the tissues 

 of the carpel; fertilization consisting of a double process: not only does the 

 sperm-nucleus fertilize the egg-nucleus to form a diploid zygote which develops 

 into the embryonic sporophyte in the seed, but another simultaneous fertilization 

 in the same female gametophyte results in a triploid or higher polyploid nucleus 

 which in many members of the class produces a nutritive tissue called endosperm 

 closely associated with the embryonic sporophyte. 



A stupendous array of about 200,000 species including all of the important 

 sources of food and fiber, and including all the plants which the man in the street 

 calls flowers. 



Fig. 24: Typha lati folia: a, pistillate spike, X %; b, single compound pedicel of 

 pistillate spike, X 20; c, upper part of plant, showing distichously arranged leaves 

 and young contiguous spike with staminate flowers (above) and pistillate flowers 

 (below), X ':,; d, somewhat older spike, X %; e, variation in spike size X %; f, 

 4-celIed pollen grains; g, group of compound pedicels of pistillate spike, X 4; h, young 

 pistillate flowers, the pedicel not yet elongated, and fascicled hairlike bracts, X 12; 

 i and j, stamens on branched filaments, X 6; k, staminate bracts, commonly white 

 or brown-tipped. X 6; 1, oblanceolate fleshy stigma, X 12; m, sterile pistillate flower 

 with ellipsoid aborted ovary tipped by rudimentary style, the surrounding hairs, like 

 those of fertile flower, originating at base, X 4; n. sterile ovary, light-brown, X 12; 

 o, pistillate flower with mature functional ovary, X 4. (From Mason, Fig. 8). 



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