Assignment: Summary

Introduction

The following article has been written Witt Taylor, Melanie L. DeVore and Kathleen B. Pigg. They discuss in this article a new type of seed namely Nymphaeaceae which are found in the regions of Late Paleocene Almont Flora located in North Dakota state of United states of America. They discuss about the seed which is a part of the water lily family. The botany techniques used to understand the characteristics of this seeds is plant anatomy and plant morphology.

Plant anatomy is used to study the internal structure of the seeds. Plant morphology is used to study the external structure of the seeds. Cell biology is further practiced to study the physiological properties of the study. The details of the paper are further discussed in the next section.

The prime reason to conduct this search was to relate the seed with other species and identify the family to which it belongs. Secondly the similarities and differences with other seeds are compared in this paper.

Discussion

The writers of this paper Pigg, DeVore and Taylor researched and described a new type of seed which is a part of the water lily family namely Nymphaeaceae, which were extracted from Late Paleocene Almont Flora of central North Dakota, USA.

The seeds shape is oval and is 3 mm wide and 5 mm long. The operculum is apical and raphe is prominent lateral. Palisade is the main component of the outer surface with cells similar to shingle which are 3 mm wide and 40 mm high and the margins are as smooth as papillae. Several cells separate micropyle and raphe. Extant Euryale is not similar to the seeds but raphe morphology, seed coat and epidermal cells differ.

History of seed

The history of the seed is quite old, it first appeared in Early Cretaceous and its symptoms relate to seeds of today as well such as taxa based seeds. In order to examine the seeds they are preserved anatomically and silicified. The type of specie which was found was Susiea newsaleamae.

Characteristics of the seed

Seeds oval to barrel shaped, with prominent lateral raphe that protrudes outward from the seed and is subtended by a ''pinch'' of adjacent cells; operculum apical, surrounded by shallow furrow, covering micropyle but not hilum; micropyle and hilum separate; seed coat composed of uniseriate outermost layer of palisade cells with smooth margins lacking papillae, underlain by uniseriate layer of cuboidal cells, next region of parenchymatous cells making up bulk of seed coat; innermost uniseriate layer of cells with highly digitate cell margins; embryo cavity apical, small; perisperm abundant (Womersley, 1980, pp. 1 - 137).

Seeds 5 mm long 3 mm wide; operculum 1 mm across; cells of outer seed coat 40 mm high 3 mm wide, with smooth cell margins lacking papillae; cells of cuboidal layer 25-35 mm high 3 mm wide; central region of seed coat estimated to be 1.0-1.3 mm thick, innermost digitate cells 120 mm high 3 mm wide; embryo cavity 0.9 mm high 3 mm wide, immediately below the micropyle; cells of ...