LESSON 32.] TRILLIUM, OK BIRTHROOT. 103 



colored petals refer our plant to the third, marked H- - *-. Under 

 this we have four lines in a row, beginning with " Pistils" or "Pistil." 

 As our plant has a compound pistil, with three styles or stigmas, but 

 the ovaries all united into one, which is three-celled, and with many 

 ovules (or at length seeds) in each cell, it cannot belong to the first, 

 -which has numerous pistils ; nor to the third, which has only one or 

 two seeds in each cell ; nor to the fourth, which has a one-celled 

 ovary ; but it docs accord with the second line. One step only 

 remains ; which the three styles or stigmas and the three leaves in 

 a whorl decide, directing us to TRILLIACK^E, page 401. 



5G2. On referring to that page, we learn that Trilliaceoe is a sub- 

 order of the order SMILACE^E, and that it comprises two genera. 

 Our plant accords with the first genus, TRILLIUM, which is fully 

 characterized on p. 4G3. 



563. We have now only to ascertain the species. The species of 

 Trillium are arranged in two principal sections. The first (1) 

 has a sessile (i. e. stalkless) flower, with long and narrow petals. 

 The second ( 2) has the flower raised on a peduncle; this includes 

 our plant. The species we have in hand has a slender and nearly 

 erect peduncle ; so it falls into the division * * ; it also has sessile 

 and abruptly pointed leaves, which bring it under the subdivision -i~ . 

 The shape, size, and color of the petals, as well as the other partic- 

 ulars mentioned, determine the species to be T. ERECTUM. 



564. The student residing west of New England will also be 

 likely to find another species, with similar foliage, but with larger, 

 pure white, and obovate petals, turning rose-color when about to 

 fade. This will at once be identified as T. grandijlorum. And 

 towards the north, in cold and damp woods or swamps, a smaller 

 species will be met with, having dull-green and petiolcd leaves 

 rounded at the base, and rather narrow, wavy, white petals, marked 

 with pink or purple stripes at the base : this the student will refer 

 to T. erytkrocarpum. But the species principally found in the east- 

 ern parts of the country has a short peduncle recurved under the 

 leaves, so as nearly to conceal the much less handsome, dull while, 

 flower : this belongs accordingly to the first division under 2, and 

 is T. cernuum, the Nodding Trillium or Wc&e-'Jtobin* 



565. Whenever the student has fairly studied out one species of 

 a, genus, he will know the others when ho gees them. And when 

 plants of another genus of the same order are met with, tlie order 

 may generally bo recognized at a glnnce, tVum the family resem- 



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