22 



ACADEMIC BOTANY. 



rio. 11. — A, single plant of Ciiroococcug rufescenty X* 

 B, same, two cells forming: inside. C, same, four cells, 

 read.v to bnrst. D, Bed Snow — Prolococctts nivalis^ Xt 



has no roots, stems, nor leaves ; but it has parts equiv- 

 alent to them (8). Its cellulose (Fig. 11, A), moved by 

 the protoplasm within, absorbs materials from the water, 

 the air, and the earthy matter they contain, just as 

 shrubs and trees absorb them through the root, stem, and 



leaf. These materials 

 are called Pabulum 

 (L. food). The pro- 

 toplasm receives the 

 pabulum transmitted 

 to it by the cellulose ; 

 with unerring exaeti- 



forming many cells. B, young plant of Pediaslrum tudc it ScleCtS, COm- 

 granvlnlum before tlie formation of cellulose; two , . ,. ' , 



cilifB, whicli are mere projections of the surface (film) binCS, QlgeStS tue 



of protoplasm. various substauccs ; 



it endows them with its own powers ; it grows. 



39. Single Reproduction. Cell-division, Fission. — This 

 little cell has no flowers, but it has parts equivalent to 

 them (8). The mother-cell divides interiorly into several 

 daughter-cells (Fig. 11, B, C, D). Each daughter-cell 

 invests herself with a primordial utricle ; the mother-cell 

 bursts and dies ; the daughter-cells escape as spores. Each 

 spore at first has no cellulose ; in some species the pri- 

 mordial utricle is protruded in the form of cilise (Fig. 11, 

 E) maliing zoospores, as in Vaucheria. These frisk and 

 frolic, like those of Vaucheria, for a while ; then they with- 

 draw their cilise, form a wall of cellulose (as in Fig. 1, E); 

 each repeating the simple family history, performing within 

 itself all the functions of seed, plant, and flower. This earliest 

 form of parentage (birth through a mother-cell alone) is called 

 Oell-division. It is called Fission when the mother-cell di- 

 vides into two parts, creating two daughter-cells. 



40. Single Keproduction is sometimes called Asexual or neuter 

 by botanists ; but this is an ill-chosen and contradictory term, and 

 should be avoided, even in the flower-world. In the Protococcus, 

 and in one form of the Vaucheria and CEdogonium (Pig. 1, D, E, 

 F), the whole of reproduction is begun and developed in a mother- 

 cell without foreign aid. We see the same thing very often in 

 some of the Orders of Phanerogamia, — Hemp, Coelebogyne, and 

 Bryony (Pig. 184), which are dioecious; the female flowers fre- 

 quently produce perfect seeds (developing into perfect plants) with- 

 out the aid of pollen. In Phanerogamia this mode is dignified 



