. African Ixodoidea. l. Ticks of the Ticks -- Sudan. fijrrow is to prevent the spilling back into the host's voiind of any blood already in the pharynx. The tonguelike process also appears to play an essential part in the mechanism of ejection of salivary fluid into the blood as it is being ingested. Since the salivary fluid is discharged into the distal region of the buccal canal, it is assumed to reach the wound in the host (and thus might transmit disease-causing organisms contained in it). As stated above, Bertram's study has considerable practical value, but must be read in its e
. African Ixodoidea. l. Ticks of the Ticks -- Sudan. fijrrow is to prevent the spilling back into the host's voiind of any blood already in the pharynx. The tonguelike process also appears to play an essential part in the mechanism of ejection of salivary fluid into the blood as it is being ingested. Since the salivary fluid is discharged into the distal region of the buccal canal, it is assumed to reach the wound in the host (and thus might transmit disease-causing organisms contained in it). As stated above, Bertram's study has considerable practical value, but must be read in its entirety to be fully appreciated. It should be noted that Snodgrass (194-8) refers to the tongue- like process as the labrum in his noncommittal review of Bertram's findings and conclusions. Alimentary canal; We now retxu-n to Christophers' (1906) study of 0. savignyi, and it is interesting to note that he found the pharynx to open into the floor of the '*mouth" (buccal canal) in contrast to Bertram's observation on 0. moubata, mentioned above. At any rate, the pharynx leads to a narrow, straight esophagus. The latter, after perforating the central ganglion, enters the enormous saccular midgut, which, with its diverticula, forms the great bulk of body contents. Posteriorly, an extremely fine canal, which appears to be a fionctionless rudiment, joins the midgut with the rectal ampulla (but in 0. moubata even this is absent and the alimentary canal ends in a completely closed sac separated from the rectal ampulla) (see below), Esophagvts and proventricular fold. The esophagus, a short, straight tuiDe perforating the centraTganglion in its course from pharynx to alimentary sac, is lined with a layer of clear columnar cells with small nuclei. The irregular outlines of these cells are mutually adapted to one another in a dovetailing arrajige- raent. At the juncture of the esophagus and large blood sac there is a small solid organ. This organ, in section, consists of a thick fold
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