PB ACTIO AL BOTANY. 



PLATE XIII. 



1, Abies Canadensis, part of a branchlet with staminate 

 aments ; la, the upper part of a branchlet terminated by 

 a fertile strobile; both the natural size; 12», carpellary 

 scale of a fertile ament, with its bract ; !<?, the carpellary 

 scale of a fertile ament, inside view showing its two ovules 

 at the base ; both figures magnified. 



2, Cupressus thyoides, the ripe strobile, of natural size. 



3, Juniperus communis, the fruit, formed of a few fleshy 

 scales, and containing 2 or 3 bony seeds, natural size. 



4, Taxus baccata, a pistillate flower ; 4(^, a sterile ament ; 

 both magnified ; 45, fruit. 



5, Symphoricarpus foetidus, the hooded-sh ell-form spathe 

 enclosing tlie globular spadix, reduced in size ; ha., a flower 

 magnified. 



6, Arisaema triphyllum, the spadix in fruit, about the 

 natural size. 



Y, Lemna minor, magnified plant, bearing a diandrous 

 perfect flower apparently, but really two sterile flowers — 

 that is, stamens — and one fertile, which is a pistil ; la, the 

 urn-shaped spathe with its three flowers, highly magnified. 



8, Najas flexilis, a branchlet of the much-branched stem, 

 which is thread-like and 6 to 12 inches long, natural size ; 

 8a, a fertile flower, with leaves, magnified. 



9, Potamogeton natans, part of the plant, reduced in 

 size ; 9*2, a flower of the natural size. 



10, Alisma Plantago, part of the panicle, of natural 

 size ; 10^, a flower ; 102>, the calyx with the pistils ; 10c, 

 a pistil ; all variously magnified. 



11, Yallisneria spiralis, the fertile flower, sessile in a 

 tubular spathe, borne on a very long scape, which is pre- 

 served in part ; 11«, the steiile flowers, crowded in a head 



