S50 



NATURAL HISTORY OF PL.iNTS. 



Sanguigorla (Poferiitm) polygama. 





i 





^y 



certain species have only ten or twelve, or even five or six.' Thus 

 tlu' aillorences formerly^ pointed out between these two genera 

 gradually disappear, and they become quite inseparable. 



Thus constituted, this generic group contains about fifteen species 

 found native in all the temperate and warm regions of the northern 



hemisphere.'- Nearly all are herba- 

 ceous and perennial ; one alone is 

 j^ %^ "- "^ rr^ « JL^-ft^ annual, and has been made the type 



^ W^flFf 7 ^f '^ distinct genus under the 



name of Poiendium.^ P. spinosum'^ 

 is frutescent, and its aborted 

 branches are to some extent trans- 

 formed into spines. Its floral 

 receptacle becomes thicker and 

 fleshier than in the other species. Hence the generic name of Sar- 

 copofcrimn" proposed for this species. 



The flowers of Poli/hpis^ have the receptacle and indefinite stamens 

 of Poterium. The calyx has from three to five leaves, slightly im- 

 bricated when young, but, as a rule, finally becoming valvate. The 

 carpels are usually solitary ; but this is not constant, some flowers 

 possessing two or three carpels ; they are in other respects those of 

 Poterium. The receptacle forms a sac around them in the fruit, and 

 is marked by longitudinal projecting lines, here and there inter- 



Fio. 405. 

 Hermaphrodite flower 



Fig. 406. 

 Heptandrous flower. 



' So too there arc true Sanguisorhas whose 

 specific name indicates the general number of 

 stamens, sudi as S. dodecandra Mokett., dec- 

 andra Wall., &c. These stamens are also 

 longer. In the tpicies oF the section or sub- 

 genus Poterium, such as P. Sanginsorha L., 

 ancislroides Desf., &x:., there are almost always 

 male flowers at the base of the spike, female 

 flowers at the apex, and between them a variable 

 number of completely or incompletely herina- 

 phrcnlite flowers with ten or twelve stamens (fig. 

 405) or even only half a dozen (fig. 406) ; they are 

 then shorter than in the male flowers. In the 

 hennaphri)dite flowers the gynaiceum may have 

 a sterde ovary, but the style and stigma are 

 pretty well developed. In many species, too, 

 the expansion of the flowers begins as de- 

 scribed in the text. The fruit is the organ sidj- 

 ject to the g^eate^t variations in Poterium ; and 

 SpaCH, in founding subdivisions in this group, 

 has chiefly regarded the outer surface of the in- 

 dusiiiu), whether reticulate, rugose, muricato. 



warty, or veined, or more or less marginate or 

 four-winged. 



- DC, Prodr., ii. 593-595.— Walp., Rep., 

 ii. 44 ; Ann., i. 282 ; iii. 855 ; iv. 665.— Desf., 

 Fl. Atlant., ii. 346, t. 251.— Toke. & Ge., Fl. 

 N. Amer., i. 428. — Spach, Eevis. Gen. Pote- 

 rium, Ann. Sc. Nat., ser. 3, v. 31. — Geen. & 

 Gomi.,Fi. deFr.,\.562. — A.GEAy,l/ct«. of Pot., 

 ed. 5, 150.— Chapm., Fl. S. Unit.-States, 122.— 

 Haev. & SoND., Fl. Gap., ii. 292.— Miq., Mns. 

 Lvgd. Bat., iii. 38. — Thw., Fnum. PL Zeyl., 

 102.— A. Be., App. Sort. Berol. (18G7), 10. 



^ Spacii, Ann. Sc. Nat., ser. 3, v. 43 (San- 

 guisorba annua Tore. & Ge., Fl. N. Amer., i. 

 429; — Poterium anntiitm NUTT.). 



" L., Spec, 1411.— DC, Prodr., n. 1 (sect. 

 Leiopoterium). — Sibth., Fl, Grcec, t. 943. 



' SPAcn, Ann. Sc Nat., loc. eit. 



« K. & Pay., Prodr., Fl. Per. et Chil., 34, t. 

 15. — DC, Prodr., ii. 591. — Endl., Gen., n. 

 6377.— K. IT., Gen., 623, n. 55. 



