Stratigraphy
Lithostratigraphic Units:
These are bodies of sedimentary (and other) rocks whose boundaries are based in changes of lithologyFormation. Formations may contain smaller units, called "Members" and "Beds." Additionally, Formations may be clustered together in larger units, called "Groups" and "Supergroups."

Lithostratigraphic grammar:

• Each formation has a formal, unique name (with the word "Formation" capitalized): Morrison Formation, Dinosaur Park Formation, Calvert Formation, etc.
• In some formations, the lithology may be used instead of the word "Formation", but must still be capitalized: Solnhofen Limestone, Bright Angel Shale, etc.
• Smaller and larger lithostratigaphic units follow the same rule, but MUST include the name of the type of unit (capitalized): hence, Brushy Basin Member (of the Morrison Formation), or Judith River Group.

Chronostratigraphic Units:
These are bodies of rocks whose upper and lower boundaries are based on time rather than changes of rock type. This is a fairly esoteric concept, and you will likely more often encounter geochronologic (i.e., time) units in your reading than these units. Still, should you refer to them, you'll want to use the correct grammar.

The fundamental unit of chronostratigraphy is called the System. Systems are broken down into smaller units called "Series", which themselves are broken down into even smaller units called "Stages." In principle Systems are clusetered into larger units ("Erathems" and "Eonthems"), but the latter terms are rarely encountered outside of Historical Geology and Stratigraphy classrooms.

Chronostratigraphic grammar:

• Each System has a one word formal name, followed by the word "System" (capitalized).
• Also, each Stage has a one word formal name, followed by the word "Stage" (capitalized).
• Some Series are occasionally given a one word formal name, but more often are named to represent the physical part of the System they are in: Lower, Middle (if any), or Upper. These words MUST be capitalized, as they are a formal part of that name.
• Since this is a dinosaurs class, I'll just give you the formal names for the various chronostratigraphic units you're most likely to encounter. These are arranged in proper stratigraphic order, with the lowest on the bottom:

Cretaceous System
Upper Cretaceous Series
Maastrichtian Stage
Campanian Stage
Santonian Stage
Coniacian Stage
Turonian Stage
Cenomanian Stage

Lower Cretaceous Series
Albian Stage
Aptian Stage
Barremian Stage
Hauterivian Stage
Valanginian Stage
Berriasian Stage

Jurassic System
Upper Jurassic Series
Tithonian Stage
Kimmeridgian Stage
Oxfordian Stage

Middle Jurassic Series
Callovian Stage
Bathonian Stage
Bajocian Stage
Aalenian Stage

Lower Jurassic Series
Toarcian Stage
Pliensbachian Stage
Sinemurian Stage
Hettangian Stage

Triassic System
Upper Triassic Series
Rhaetian Stage
Norian Stage
Carnian Stage

Middle Triassic Series
Ladinian Stage
Anisian Stage

Lower Triassic Series
Olenekian Stage
Induan Stage

(Note that the Cretaceous System is only divided into an Upper Cretaceous and Lower Cretaceous System. Although some geologists refer to a "Middle Cretaceous", that is not a formally recognized unit. If you want to talk about the upper part of the Lower Cretaceous and the lower part of the Upper Cretaceous, it is best to refer to it just as the "mid-Cretaceous."

Geochronologic Units:
These are the time units that correspond to the chronostratigraphic above. You are probably going to encounter these more often than chronostratigraphic units. Unfortunately, some scientists get sloppy in their work, and will sometimes mix and match these different concepts. So just a reminder: when talking about time, use geochronology; when talking about the bodies of rock deposited in that time, use chronostratigraphy.

The fundamental unit of chronostratigraphy is called the Period. Periods are broken down into smaller units called "Epochs", which themselves are broken down into even smaller units called "Ages." Periods are clustered into even bigger chunks of geologic time called "Eras" and "Eons."

Geochronologic grammar:

• Each Period uses the same one word formal name as the System upon which it is based, followed by the word "Period" (capitalized).
• Also, each Age uses the same one word formal name as the Stage upon which it is based, followed by the word "Age" (capitalized).
• Some Epochs have a one word formal name, but more often are named after the time within the Period that the represent: Early, Middle (if any), or Late. These words MUST be capitalized, as they are a formal part of that name. Also note, the Late Cretaceous Epoch is a formal chunk of geologic time; avoid the inaccurate phrase "late Cretaceous Period".
• Since this is a dinosaurs class, I'll just give you the formal names for the various geochronologic units you're most likely to encounter. These are arranged in proper stratigraphic order, with the oldest on the bottom:

Cretaceous Period
Late Cretaceous Epoch
Maastrichtian Age
Campanian Age
Santonian Age
Coniacian Age
Turonian Age
Cenomanian Age

Early Cretaceous Epoch
Albian Age
Aptian Age
Barremian Age
Hauterivian Age
Valanginian Age
Berriasian Age

Jurassic Period
Late Jurassic Epoch
Tithonian Age
Kimmeridgian Age
Oxfordian Age

Middle Jurassic Epoch
Callovian Age
Bathonian Age
Bajocian Age
Aalenian Age

Early Jurassic Epoch
Toarcian Age
Pliensbachian Age
Sinemurian Age
Hettangian Age

Triassic Period
Late Triassic Epoch
Rhaetian Age
Norian Age
Carnian Age

Middle Triassic Epoch
Ladinian Age
Anisian Age

Early Triassic Epoch
Olenekian Age
Induan Age

(Note that the Cretaceous Period is only divided into an Late Cretaceous and Early Cretaceous Epoch. Although some geologists refer to a "Middle Cretaceous", that is not a formally recognized unit. If you want to talk about the later part of the Early Cretaceous and the early part of the Late Cretaceous, it is best to refer to it just as the "mid-Cretaceous."

Taxonomy
Rules for names in Linnean Taxonomy:

• Genera have one word names (e.g., Panthera, Homo, Ginkgo, Tyrannosaurus);
• The genus name is always Capitalized and italicized (or underlined if you don't have access to italics);
• Species have two word names, the first part of which is the same as the genus name (e.g., Panthera leo, Homo sapiens, Ginkgo biloba, Tyrannosaurus rex)
• The genus name is ALWAYS Capitalized, the second part ("trivial nomen") is ALWAYS in lower case, and the name is ALWAYS italicized or underlined;
• Species names can be abbreviated by using only the first letter of the genus name, followed by a period (NEVER by a hyphen): H. sapiens and T. rex are correct; H. Sapiens or T-Rex are WRONG!!;
• All taxon names other than species have one word names, which are Capitalized; all taxon names other than genera and species are in roman letters (i.e., they are never italicized/underlined): Dinosauria, Tyrannosauridae, Animalia; not Dinosauria, tyrannosauridae, or animalia.

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