BOTANY. 59 



united in club-sbaped expansions or receptacles, situated at tlic end or 

 margins of tlie fronds. In germinating, the nucleus bursts the episporc or 

 outer covering of the spore, and sends out filamentous processes. PI. 54, fig. 

 36, Laminaria digitata ; fig. 37, L. saccbarina witli cellular tissue and fruit. 

 Fucus vesiculosus {fig. 38). 



Sub-order 5. Characea : Avater plants formed of parallel tubes, Avbicb arc 

 sometimes incrusted Avitb carbonate of lime ; reproductive organs are of 

 two kinds : a, a round red globule consisting of eight valves which inclose 

 cells of different kinds, containing granular matter and peculiar spiral fila- 

 ments or phytozoa ; 6, an oval nucule formed by a large central cell or 

 spore, with five elongated cells wound spirally round it, surmounted by five 

 teeth. Some consider the globule as an antheridium, and as equivalent to an 

 anther. 



Order 2. Fungi, the Mushroom Family. The plants belonging to this 

 order consist of cells, sometimes round, sometimes elongated, in the form of 

 filaments, either placed closely together, or separated. They are variable 

 in their consistence, being soft or hard, fibrous or gelatinous, fleshy or 

 leather3\ They never contain green gonidia, like Lichens, and they rarely 

 grow in water. There exists a vegetative system, called spawn or my- 

 celium, formed of elongated, simple, or articulated filaments, concealed 

 within the matrix, or expanded over its surface, from which varied forms 

 of fructification proceed. The mycelium occurs either in a filamentous, a 

 membranous, a tubercular, or a pulpy form. The reproductive organs con- 

 sist of spores or spherical cells (usually four, or some multijile of four), 

 which are either attached to the cellular tissue, and supported often on 

 simple or branched filamentous processes, called sporophores or basidia ; or 

 are contained in thecoe, cystidia, or asci, accompanied by bodies called 

 antheridia, or paraphyses ; in the latter case the term sporidia is sometimes 

 applied to the spores. The spoi'ophores sometimes end in delicate cells, bear- 

 ing the spores, and called sterigmata. In the Agarics, or ^lushrooms, 

 which are among the best known fun 2:1, there is observed first a roundish 

 protuberance on the mycelium. This swelling .is called the volva, or wrap- 

 per, and it gradually enlarges, containing in its interior what appears 

 afterwards as the agaric, with its reproductive bodies. When the volva is 

 ruptured the fully-formed agaric is seen, consisting of an upper rounded 

 portion, called the pileus, or cap, supported on a stalk or stipes. On its 

 under surface is situated the hymenium, or the part where the spores are 

 produced, covered at first by a thin membrane, called a veil (indusium or 

 velum), which is ultimately ruptured ; and when the rupture takes place at 

 the edge of the pileus, an annulus or ring is left on the stipes. The 

 hymenium, or the part on which the organs of reproduction are placed, 

 consists in the agaric of cellular plates, lamellae, or gills, radiating from the 

 centre. In other genera of fungi it consists of tubes or solid colunnis, or 

 fleshy or gelatinous matter. Sometimes the hymenium is on the upper 

 surface of the fungus. Cellular plants, often growing on decaying organic 

 matter, generally very transient, and presenting various colors, and found in 

 all parts of the world. 



59 



