926 IX. MUSCI. 



granules; water dissolves the mother-cell, and frees the antherozoid, which by means 

 of its vibrating hairs reaches the gaping mouth of the archegonium. 1 



The AECHEGONIUM or female organ originates, like the antheridium, as a cell, 

 which by subdivision develops a cylindrical cellular body with a rounded top, tra- 

 versed by a canal. As its walls elongate, the lower part of the archegonium dilates, 

 till, when mature, it becomes flagon-shaped, and at the same time its tubular apex 

 has expanded into a funnel-shaped terminal orifice. The cavity of the archegonium 

 contains a nucleus (a free cell) immersed in mucilage. The nucleus, after fertiliza- 

 tion of the archegonium by an antherozoid, elongates and becomes cylindric, the 

 archegonium itself at the same time increasing both in length and breadth ; but 

 the nucleus being developed far more rapidly than the archegonium, finally ruptures 

 this transversely, carrying up its upper part as a conical cap (calyptra), and leaving 

 its lower part as a sheath (vaginule) surrounding the base of the nucleus, which now 

 forms a slender bristle. This bristle goes on elongating, still capped by the calyptra, 

 till it has attained its full height, when the upper part within the calyptra swells 

 and forms the capsule (theca or urn], commonly called the fruit of the Moss. The 

 rest of the bristle is the pedicel or neta of the capsule. 



The CAPSULE is usually ovoid or cylindric, sometimes spherical (Pkascum), or 

 angular (Potytrichum), rarely compressed on one side and unequal. It may remain 

 entire (PAosctm), or split into four segments united at the top (Andrcea) ; but in most 

 other Mosses it dehisces transversely above the middle. This detached portion is 

 named the operculum of the capsule. The base of the capsule is usually narrowed 

 equally into the seta ; but sometimes there is a symmetrical oblique or gibbous 

 swelling at the junction, called apo])hyxis. In Andrcea and Archidium the apex of 

 the branch at the base of the seta is swollen and fleshy, forming a pseudopodium, 

 as in 8pluign<>a>. Between the margins of the operculum and of the capsule there 

 often exists an intermediate organ, called the annulus, composed of one or several 

 rows of very hygrometrical cells, the rapid growth of which facilitates the detach- 

 ment of the operculum. The mouth of the capsule is naked, or furnished with a 

 peristome consisting of 1-2 rows of lanceolate or filiform (Dawsonia) appendages or 

 teeth, which are definite in number (4, 8, 16, 32, 64). When the peristome is 

 simple, it usually originates in the loose tissue which lines the inner surface of the 

 urn ; when it is double, the inner is a prolongation of the sac (sporangium) contain- 

 ing the spores. Sometimes (Polytrichum) the inner peristomium extends horizon- 

 tally from the circumference towards the centre, to form a membrane called the 

 epiphragm. The walls of the capsule are composed of an epidermal layer formed 

 of tabular small and thick cells, and of 2-3 layers of large thin and hyaline paren- 

 chymatous cells. The epidermal layer is often pierced with storaata, especially at 

 its lower part, as well as at the neck and apophysis. 



The SPORANGIUM is enclosed in the capsule; it is composed of a membranous sac 

 which lines the cavity of the capsule, and whose base is drawn up like the finger of 

 a glove over a central axis (columella}. A loose tissue, or of jointed and sometimes 



1 I am unable to make the structure of the organs of from which I have widely departed in the description 

 Mosses clear by a literal translation of the original, of the development of the archegonium. ED. 



