The original text has been retained as printed, with some exceptions. Illustrations have been moved from within paragraphs to nearby spots between paragraphs. Page numbers from the printed 1901 edition are indicated like this: "[pg235]".

Many of the biological classification schemes shown in this book were printed with large curly brackets "{" extending several lines high. For example, on page 18, a classification scheme was printed similar to this:

except that the three "{" were not printed, but were replaced by a single tall "{". This typography does not generally work well in current electronic books. Therefore, tables or schemes of this sort have (except on page 18) been replaced by a different format (nested list) employing rearrangement and indentation, without curly brackets—like this:

There are rare instances when this could cause confusion. For example, the partial paragraph that preceeds the page 18 example being discussed:

refers to a bracket no longer present in the electronic version, and "left" and "right" are perhaps no longer meaningful. Also, the captions heading most of these taxonomies use the word "table", which is retained, although it is now wrong, and should be interpreted as "taxonomy" or "list". Return to footnote †.

As mentioned on page 29 of the book, typography was used in a specific way to visually distinguish various taxonomic classes. Some of the forms used herein do not work well in some current e-reader applications. For example, small-caps do not currently work well in many epub reader applications. Therefore, small-caps typography is herein reinforced with an underline. Here are examples of most of the variants: BOLD UPPERCASE SMALL; BOLD UPPERCASE LARGE; Bold Italic; Bold; UPPERCASE SMALL; Small Caps; and Italic.

Page 102: "flagelloete Infusoria" was changed to "flagellate Infusoria" to match the corresponding index entry.

Page 116, Table showing the classification of Hydrozoa: genera and species were printed in one table column without distinction. These have been recast into the usual style used in this electronic edition. Also, for the purpose of this recasting, it has been assumed that a taxonomic "Division" can be taken to be an informal subset of a "Family", at least in this specific taxonomy.

Page 150: in "The strictures forming the lobes", changed "strictures" to "structures".

Page 154: changed "rhododaciyla" to "rhododactyla".

Page 172: changed "perisaltic" to "peristaltic".

Page 188: in the table showing the classification of the Mulluscoida, there are grouping words such as "Articulata", "Inarticulata", and "Flustrina", which are not labeled as to whether they are taxonomic "Family", or some other class. The transcriber has chosen to label them "Set", which term is not elsewhere used in the book to denote a formal taxonomic class. The same sort of thing is done on a few other pages, e.g. on page 240, for the group "Free-swimming Forms", part of Suborder Macrura.

Page 196: "Phyllopora" changed to "Phyllophora"—a guess.

Page 216 (facing), Plate LV.: "Ophiocoma oethiops" changed to "Ophiocoma Æthiops".

Page 233: "rows" to "Rows", in "rows of tube-feet lie near together,".

Page 362: "fdation" to "foundation" in "greenish-white nacreous fdation".

Page 486: the index entry "Pacific faunal divisions" had no page number. The number "311" seems correct, and has been inserted.

Index, "Endendrium ramosum, Plate XLI." entry is removed, and "Plate XLI" is added to entry "Eudendrium ramosum".

Index, entry "Ventricosa" changed to "Ventricose".

Corrigenda: The corrections listed therein have been applied to the text. In addition to the listed corrections, there were two other instances of "lunales", on pp 225 and 226, now changed to "lunules"; also "lunale" to "lunule" on p 225.