116 LIVERWORTS. [BOOK i. 



this, when the anther has arrived at a state of maturity, 

 escapes through an irregularly shaped opening, which bursts 

 at the extremity." Von Martius suspects these to be analo- 

 gous to the sporangia of Azolla. 



In Monoclea and Targionia organs nearly analogous to those 

 of Jungermannia are formed for reproduction. In Targionia 

 the antheridia are represented by M. Montagne as being 

 embedded in discs very like the shields of Lichens. (Ann. 

 Sc., n. s. ix. 100.). 



In Marchantia the frond is a lobed flat green substance, 

 not dividing into leaves and stems, but lying horizontally 

 upon the ground, and emitting roots from its under surface. 

 The organs of reproduction consist, firstly, of a stalked fungus- 

 like receptacle, carrying on its apex a calyptra, and bearing 

 sporangia on its under side ; secondly, of a stalked receptacle, 

 plane on the upper surface, with oblong bodies embedded 

 vertically in the disc, and called anthers ; thirdly, " of little 

 open cups (cystulce), sessile on the upper surface of the fronds, 

 and containing minute green bodies (gemma), which have the 

 power of producing new plants." The first kind is usually 

 considered a female flower, its spores being intermixed with 

 elaters ; the second male, and the third viviparous apparatus. 

 In the opinion of many modern botanists, the granules of 

 both the first two are spores : about the function of the last 

 there is no difference of opinion. Mirbel considers the first 

 two to be male and female; but, whatever their functions 

 may be, in structure there is but little analogy between them 

 and the organs of more perfect plants. Meyen describes the 

 so called spermatic animalcules, resembling the genus Vibrio, 

 as occupying the interior of each grain of the supposed pollen 

 in Marchantia polymorpha. (Comptes Rendus, vi. 533). They 

 are figured by him in the Annales des Sciences, n. s. x. 319, 

 t. 3, from Marchantia polymorpha, Chara vulgaris, Sphagnum 

 acutifolium, and Hypnum triquetrum. Their real nature 

 has been already explained. 



In Anthoceros, while the vegetation is the same as in Mar- 

 chantia, the organs of reproduction are very different. They 

 consist of a subulate column, issuing from a pericha3tium 

 perpendicular to the frond, and dividing half way into two 



