776 Botanical Microtechnique 



Fig. 15.6— Fei til i/,atioii in Liliitin regale; a, sperm and egg in conlaci: h. spcini 



appressed to egg, zygote wall evident. 



THE EMBRYO, SEED, AND FRUIT 



Embryology is usuall) neglected in elementary courses, in part 

 because of the high cost ol an adecjuate series of slides. Slides of early 

 stages of embryo development are comparatively expensive to make, 

 whereas the manufacture of slides of nearly mature embryos is more 

 jMoductive. The embryo of lily is large and not diliicidt to j)repare. 

 Use species that produce seed, such as Lilluiii regale or /.. lemiifoliin)). 

 Cut the ovaries into disks not over L! mm. thick and dixide loneitu- 

 dinally iiuo three sectors, each sector containing one locule. Good 

 lixation ol the cnibr)o can be obtained consistently xviih Allen- 

 Boiiin II. liaxing the formaldehyde solution reduced to 5',. Section 

 transversely at 15 to IS ii. Ilu flat developing seeds are in long tiers, 

 and a block yields many gootl sections, all cut longitudinalh ^vith 

 the axis of the embryo (Fig. 15.7) . If six or eight sections are moinited 

 on cadi slide, most ol ilie slides \v'\\\ contain at least one acciiiatelv 

 cut ciiibiNo. Ihe most sal islac loiN sl;iin is iron hemalowlin \vith a 

 ver\' li<'lu cotinierstain ol last tireeii, which stains ihc cell xvalls ol 

 the embryo. 



