The Anatomy and Histology of the Head, Gut and Associated Structures of Typhlocyba ulmi.



The arrangement of the sclerites forming the head-capsule, and the internal anatomy of the head are described. The tentorium consists of one transverse and two longitudinal bars. The sucking-pump is composed of a thin dorsal epipharynx and a thick, ventral hypopharynx. This structure does not represent a true pharynx. The method of suction is described. Evidence regarding the structure and function of the gustatory organ is given.

The salivary pump lies in the hypopharynx and has two large pumpmuscles inserted on it. No valvular arrangement is present at the point of entry of the salivary duct. The ejaculatory duct runs along the hypopharynx lip to the salivary canal within the stylets.

The two pairs of stylets and their musculature are described. Retort organs are present in the nymphal stages. A maxillary bar has been observed, but no mandibular lever is present.