588. What is the eye of the seed properly called?
589. When is the seed said to be albuminous? When exalbuminous?
590. Describe the albumen. Its quantity compared with the embryo. What its varieties of texture? Show examples.
591. What three parts of the embryo are mentioned?
592. Define the radicle. The plumule. The cotyledons. 594. How do these alternate with the albumen?
596. How are the monocotyledons characterized? The dicotyledons? How are these great classes distinguished by their leaves?
598. Have any plants more than two cotyledons? What of fig. 466? Of fig. 467? 468? 469?
599. What varieties in position are mentioned?
601. When does the seed sleep?
What is then its condition, or state?
602. Give examples of the great longevity of the seed.
603. How may seeds longest retain their vitality?
604. How are thistle seeds dispersed?
605. How are tick-seeds, etc., dispersed? The touch-me-not?
606. How the seeds of the squirting-cucumber?
607. What the agency of rivers? Squirrels? Birds
608. What is germination? Where may we observe the process?
610. How and why is the seed to be planted?
611. What changes take place in the material of the seed?
Show the coiled embryo in fig. 475.
Show the bursting embryo in fig. 476.
Show the liberated embryo in figs. 477, 478, 479, 480.
612. What becomes of the radicle? Of the cotyledons? How does the plumule develop? Show by the figures.
613. In what plants do the cotyledons remain below?
614. Show by figs. 481, 482, how the monocotyledon germinates.
615. What the three conditions requisite for germination?
616. Why is moisture requisite?
617. Why air? Whence comes the sugar?
618. What degrees of warmth? Give some strange exceptions.
630. What good explanation of the downward tendency of the root can you give?
621. In the lowest Cryptogams, are the parts distinct? In the higher, how is it?
622. How are they distinguished from the Phaenogams?
623. What is said of the root, stem, and leaves in Fungi, etc.?
(Note. - This chapter may he as well reviewed by the topics as by questions.)
638. Of what is all vegetable structure composed?
639. How is the cell defined? What is the primary form of the cell?
641. Mention three general types.
642. Whence do the casual forms result? Name some of them.
643. What is the size of vegetable cells?
(544. Of what length are some wood-cells and bark-cells?
645. Describe the two layers of the cell-wall.
646. How may we bring the primordial utricle to view as in fig. 568?
647. How does it appear that the cell-wall is porous?
648. What appearance does a third layer make?
649. What fills up the wood-cells? Show them by fig. 560.
650. What the appearance of pitted cells? Illustrate these cells in figs. 569 and 570.
651. What is the wonderful structure of spiral cells? Show them in figs.
571, 572, 573, 577, and in petioles.
652. Show an annular cell in fig. 574, and where else?
653. Show a scalariform cell in fig. 575, and where else?
654. What is the material of the outer cell-wall?
What are its chemical elements? What are the chemical elements of the inner cell-wall?
655. What do the cells contain? What is cytoblast? Protoplasm?
656. What is the condition of the coloring matter?
657. What is the structure and color of chlorophylle? Describe fig. 567.
658. What is the composition of the starch granules? (Figs. 579, 580.)
060. What are raphides? Show figs. 582, 583. 661. Show how the cells are multiplied.
662. What is the simplest possible form of vegetation?
663. What constitutes a tissue? Name the four tissues.
664. What the form of the cells of Parenchyma? Classify them.
666. What the form of the cells of Pleurenchyma? Two varieties.
667. In what trees do we find the pitted cells? What is fig. 579? Explain this beautiful appearance by fig. 579 bis.
668. What is trachenchyma? How are these tubes made? Show the structure of dotted-ducts in figs. 566, 576.
671. Office of cienchyma? What their nature?
673. What is said of the intercellular passages?
674. Give, finally, the import of the cell.
675. How is elevation of rank in plants indicated?
What does the " epidermal system " include?
676. What is the office of the epidermis? What its cells?
678. What are the stomata? When are they open, and when closed?
679. How many are found in the space of one square inch? Point out the stomata in the figs. 582-586.
681. What is said of the structure of hairs?
682. What is the office of glands? What varieties are there?
683. Describe the mechanism of the sting, in fig. 591.
684. How do prickles differ from spines? Describe the figures.
685. What does the " ligneous system" include?
686. Of what kind of tissue does the young rootlet consist?
687. What is the early tissue of all new growths?
688. What changes occur in the rootlet?
689. How is the increasing demand for moisture met?
690. Name the four grand divisions of plants.
691. Describe a cross-section of the stem of an Exogen.
692. Describe the pith; its composition, contents, etc.
693. Where do we find the medullary sheath? What are its vessels? Its connections? Its office?
694. Of what does the wood consist? How much grew the first year?
How much each successive year?
695. Whence is the distinction between the annual wood-circles?
697. The alburnum and duramen - how distinguished?
698. Which is the living wood? How does it become duramen? Which is valuable as timber?