36 DEPARTMENT OF AGRICULTURE

genera and numerous species belonging to the Criconematinae and other
related groups (Fig. 22 A & B). They too are ecto-parasites, puncturing
the surface of roots (Fig. 23) and other subterraneous parts with their
stylets which are strong and often extremely long. All members of this
group are short and stout and heavily annulated. In some, the annules
are provided with retrorse scales or spines, or a combination of the two.
This annulation and its armature obviously enables the members of
these groups of rather unusual looking nematodes to get the necessary
support and resistance in the soil while they press their stylets and
heads into the plant tissues. Locomotion also is possible mainly through
the use of the annules and their scales and spines. Certain types of these
groups (e.g. Hemicycliophora deMan) are of pronounced, sedentary
habit (Fig. 24). They retain their moulting skins, which make an addi-
tional protection for their bodies while quite permanently attached to a


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 Figure 24.-Hemicycliophora sp. attacking the roots of slash pine seedlings
(Pinus caribaea Morelet) near Olustee, Fla. The arrows point to groups of nema-
todes attached to blinded root tips; X 25.