ASCriDIA, STIPULES, AND BRACTS. 



93 



"9. Quinate^ \wh.en there are five leaflets radiating from the 

 same point of the petiole, ^s in PotentiUa argentea., 



10. Septinate^'when there are seven lea.ves from the same 

 point in the petiole, and so on. 



242. With regard to i-nsertien, the leaf is said to be 



1. Ainplexicaul, when its base surrounds or clasps the stem.^i 



12 4 3 5 



1 



FIG. 33. — Modes of inssrtioE. 



"2. Perfoliate /■when the base lobes of an amplexicaul leaf are 

 ranited together, so that the stem appears to pass through the 

 leaf.\ 



3 Decurrenty'^A-ien the base lobes of the leaf gro~w to the 

 «tem below the point of insertion, so that the leaf seems t-o rivn 

 doirnivards' (L§,t. decurro). 



4. Connate^heii the bases of two opposite leaves are luaited. 



5 Stdlate^ v-ferticillate, or whorled, [when several leaves are 

 aiTT.nged around tlie stem at the same node.\ 



243. It is often found necessary, in the description of a plant, to combine two 

 «3r more of tiie terms above mentioned, to express some intennediate figure or 

 quality ; thus cvate-lanceolate, signifying; between ovate and lanceolate, &c. '. 



a. The Latin preposition «k6 (under), prefixed to a descriptive term, 'denotes 

 the quality which the tenn expresses, in a lower degree, as sitbsessile/ne&vlj ses- 

 sile, sitbserratc, som_ewhat serrate, &c. ) 



§9. ASCIDIA, STIPULES, AND BRACTS. 



244. In the teazel (Dipsa<;us) of our own fields, and in the Tillandsia, or wild 

 pine of South America, thei'e are hollows at the jKiint of union between the Icaf- 

 stalK and the stem, capable of holding a considei-able amount of water. The 

 midrib and petiole of the leaves of the Aram, also, aiM3 chann-sled out in such a 

 manner as to convey water to the axil.l 



2 tS. Biit the most i-emarkable of all leaves ^re tliosc which are hollov/ed out 

 into the form of pitchers, called ascidia, \ 



a. In the San-acenia, a plant common in oui' own peat-bogs, these pitchers are 

 evidently formed; by the veiy deep channeling of the petiole, and the uniting 

 together of the involute edges of its winged margin so as to form a complete 

 vase, with a broad expansion at the top, which may he rcgai-ded as the true leaf 



