MANUAL OF NATURAL HISTORY. 511 



lindrical ribbed tube ; stamens six ; filaments 

 petaloid ; anthers 2-celled ; ovary of three 

 connate carpels ; placentae three, parietal, 

 polyspermous ; styles three, connate ; stigmas 

 2-lobed ; fruit baccate, indehiscent ; albumen 

 fleshy. Inhabit woods, and damp maritime 

 spots in tropical Africa, India, and Polynesia. 

 6. FAMILY. Pine-apples (Bromeliacese). Herbs or 

 shrubs ; stemless or short-stemmed, often epi- 

 phytic ; leaves rigid, channeled, often spiny- 

 edged ; flowers racemose or panicled ; peri- 

 anth 6-divided, in two whorls, outer persist- 

 ent, inner petaloid, marcescent or deciduous, 

 asstivation imbricate ; stamens six ; anthers 

 introrse j ovary 3-celled ; ovules 00; style 

 simple ; stigma 3-lobed, or entire ; fruit cap- 

 sular or succulent, 3-celled ; albumen fleshy. 

 All American species. The most important 

 product is the Pine-apple or Ananas, yielded 

 by Ananassa sativa. 



II. SUB-GLASS. UNISEXUAL-ENDOGENS (Monaphyseae). 

 Flowers unisexual ; with or without perianth. 



I. ORDER. HYDRALS (Hydrales). 



Flowers perfect or imperfect, not arranged on a 



spadix ; albumen none ; aquatic. 



1. FAMILY. Sea-wracks (Zosteracese). Sea-weed 

 like ; leaves grassy, thin, sheathing ; flowers 

 very minute, naked, or surrounded by three 

 scales ; stamens hypogynous ; anthers de- 



