[5c.] [Pœcilasma eburnea], carina of, lateral view of.

[5b.] [Pœcilasma eburnea], scutum, internal view of.

[6.] [Dichelaspis Warwickii], (magnified five times.)

[6a.] [Dichelaspis Warwickii], transverse section of the top of the peduncle, showing the deeply-notched end of the inwardly bent carina; magnified five times.

[6b.] [Dichelaspis Warwickii], var., scutum and tergum.

[7.] [Dichelaspis pellucida], (magnified five times.)

[7a.] [Dichelaspis pellucida], basal end of carina of, much magnified.

[8.] [Dichelaspis Lowei], (magnified nearly ten times.)

[8a.] [Dichelaspis Lowei], fork of carina of, viewed internally.

[9.] [Dichelaspis Grayii], (magnified eight or nine times.)