252 



HARDWICKE'S SCIENCE-GOSSIP. 



[Nov. 1, 1S67. 



Having made you acquainted with ^the repro- 

 ductive organs, we shall be prepared to follow out 

 their functions. As stated, the antheridium at 

 maturity bursts at the apex, and out pass the sper- 

 matozoids as a cloud of active particles ; the arche- 

 gonium equally prepares for their reception, the 

 apex of the stylidium ruptures, the edges of the 

 aperture roll back forming a trumpet-shaped orifice, 

 from which we can trace a fine duct passing down 

 to the germinal cell, and more evident now because 

 it has acquired a reddish tinge. Both Hofmeister 

 and Schimper have seen the spermatozoids within 

 this canal. 



The germinal cell, now fertilized, immediately 

 commences its own proper development, first 

 downward; perforating the base of the archegonium, 

 it fixes itself in the receptacle or apex of the stem, 

 just as a stake is driven into the earth ; then upward 

 to form the seta or fruit stalk, and the contents of 

 the archegonium being thus consumed, its delicate 

 walls are ruptured, the lower part remaining attached 

 to a process of the receptacle, as a little sheath — 

 the vaginula (fig. 265) ; the upper, carried aloft, 



Fig 265. Young fruit of Ortho- 

 trichum crispum, showing 

 Vaginula and hairy Calyptra. 



Fig. 266. Mitriform calyptra 

 of Encalypta. 



becomes the calyptra, or veil, and the seta, having 

 attained its full length, begins to enlarge at the 

 apex to form the capsule. 



The Calyptra or Veil envelops the young fruit, 

 and is thin and membranous ; it is sometimes torn 

 irregularly, or it remains even at the base, when it 

 is termed mitriform, or it is slit up on one side, 

 when we call it cucullate or dimidiate ; it is usually 

 smooth, but sometimes densely hairy (figs. 266, 267, 

 268). 



The Theca or Capsule. — This presents an infinite 

 variety of forms, but all of the greatest elegance ; 

 it may be globose, ovate, pear-shaped, or cylindric, 

 straight or arched, erect or pendulous, smooth or 



furrowed. In some it is swollen all round at the 

 base, and this part is usually of a different colour, 



Fig. 267. Cucullate inflated 

 Calyptra of Funaria. 



Fig-. 268. Cucullate conic 

 Calyptra of Fissidens. 



and is named the apophysis (fig. 269) ; in others it 

 bulges out on one side of the base, and is then said 

 to be strumose (fig. 270). 



Fig. 269. Fruit of Splachnum 

 ampullaceum with small 

 conic lid, cylindric capsule, 

 and obovate apophysis. 



Fig. 2/0. Strumose capsule 

 of Dicranum Stark ii, with 

 rostrate lid and annulus. 



Closing the mouth of the capsule, wc see a little 

 cap — the operculum or lid, in shape flat, conical, or 

 beaked ; this, at maturity, is thrown off, either by 

 the swelling of the contents or by the shrinking of 

 a contractile ring of cells interposed between the 

 lid and mouth of the capsule, which is named the 

 annulus ; well seen in the common Funaria. In 

 the genus Andresea there is no lid, aud the capsule 

 opens by splitting into four valves (fig. 271) ; and in 

 another section there is also no lid, the capsule 



Fig. 2"1. Schistocarpous 

 fruit of Andreaea. 



Fig. 272. Cleistocarpous fruit 

 of Pieuridium subulatum. 



giving exit to the spores by breaking up from decay 

 (fig. 272). These characters enable us conveniently 

 to arrange mosses in three divisions : — 



Schistocarpi— the Split-fruited Mosses. 



Cleistocarpi— the Closed-fruited Mosses. 



Stegocarpi — the Lid-fruited Mosses. 

 The wall of the capsule consists of several layers 



