Abstract
The writer established the genus Cylindrogaster in 1927 for the reception of a nematode found in cultures of rat's fæces. Its principal distinguishing features were the possession of very long buccal rods and an elongate, cylindrical, muscular first œsophageal bulb. The male possessed 10 caudal papillæ arranged in three groups disposed in a manner exactly similar to that of the caudal papilæ in many species of Diplogaster, Odontopharynx longicaudata and Tylopharynx striata.