Page:The Eurypterida of New York Volume 1.pdf/315

In tabular form the character of the three stages and the changes are as follows:

Nepionic Stage Neanic Stage Ephebic Stage Carapace Large Decreases in relative size Continued decrease With broad border Border becomes narrower Border more or less narrow and obscure   Compound eyes With immense visual node Visual node small Visual node small Position submarginal Submarginal Subcentral Visual surface relatively small Visual surface relatively small Visual surface relatively large   Abdomen Segments 7–8 Unknown 12 No distinct differentiation Distinct differentiation   Preabdomen Regularly narrowing posteriorly Widest at fourth and fifth segments   Postabdomen No epimera Long epimera All segments equally long Last segments much longer   Telson spine Very short and blunt Long and slender (?)   Sculpture None Tubercles Tubercles