The following species of Cylindrostomidae are redescribed: Cylindrosto
ma lutheri Westblad. 1955, C. micropharynx, Westblad, 1952, Monoophoru
m tubiferum Westblad, 1955, M. stiliferum Westblad, 1955 (transferred
to Einarhelmins gen. n.), Allostoma crassicystiferum (Westblad. 1952),
A. uterinum (Westblad, 1955), and Euxinia baltica Meixner, 1938. Thre
e new species are described: Cylindrostoma paralutheri, Allostoma neos
tiliferum and A. hopkinsi. A review is given on anatomy and evolutiona
ry trends in Cylindrostomidae.