IIANUNCULACEJE. 19 



tlie blade trifoliolate, with radiating pinnately compound leaflets. The 

 stem then ascends to terminate in a flower, below which we find one 

 or several leaves, from the axils of which spring branches, each also 

 ending in a flower, and so on. These floral leaves have a very short 

 petiole, with two lateral membranous appendages at the base, which 

 undoubtedly represent stipules ; and these in the cauline leaves, which 

 have a well-developed sheath, are reduced to two lateral teeth on 

 the borders of the upper part of this sheath. 



Isopyrum thalidroides L.,' has regular hermaphrodite flowers, with 

 a calyx of five coloured sepals imbricated in the bud, and a corolla of 

 five petals alternate wdth and much smaller than the sepals, cornet- 

 shaped, with the opening obliquely truncated at the expense of the 

 inner border, glandular and nectariferous at the bottom. The stamens 

 are very numerous, hypogynous, unequal, with free filaments and 

 basifixed two-celled anthers, dehiscing by longitudinal and lateral 

 clefts, rather extrorse than introrse. The gyna3ceum is composed 

 of two or three free carpels, and in the inner angle of each ovary 

 is a vertical placenta bearing the ovules, few in number, and 

 with their raphes facing one another in two vertical rows, each usually 

 of only two ovules. It is a small plant, with a horizontal rhizome, 

 from which spring young herbaceous branches bearing a 

 few alternate compound leaves, accompanied by two lateral 

 stipules. The leaves at the top of the young branch dege- 

 nerate into bracts, from the axil of each of which springs 

 a sohtary pedicellate flower ; thus is formed a small raceme. 



The petals or nectaries, already little developed in the 

 species we have just studied may disappear entirely, as in 

 many other genera of Raiumculacea — the only character 

 of any value which distinguishes Enemion biternatunr from 

 the other species of Isopyrum, with which we class it. The 

 number of ovules in each carpel is yqyj variable, there 

 being sometimes but one or two (fig. 3C) horizontal, with lUeriwhii 

 the raphe superior; or the number may be indefinite. ^c'.JJ.\gJ'" 

 Enemion inhabits North America. opened. 



•.nemion 



nil. 

 Fjg. 3(i, 



> -S/;ee., 783.— DC.,Pm/r-.,i.48,n.l.— Gben. ^ Rai-in., Journ. P/ii/s. (1820), 91, 70.— 



& GoDE., Fl. Fr., i. 42.— 0//a Adans., Fam. DC, Prodr., \. 48.— Endl., Gen., n. l7:"l.— 



PL, ii. 4i68.—Tkalicti-ella A. Richardson, Walp., A)in., ii. 11.— .\. Okay, III., t. 12.-11. 



Diet. Hist. Nat., ix., 34. Sect. Evhopynim II. II., Oen. 8, n. 21. II. Bn., Adansoiiia, iv. 



1?N., Adansonia, iv., 47. 25, 46. 



r '2 



