Date of Award

5-1943

Degree Type

Bachelors Essay

Degree Name

Bachelor of Science (BS)

Department

Biological Sciences

First Advisor

James C. Perry

Second Advisor

Donald J. Keegan

Abstract

The digestive tube proper of the Sparrow beings with the Oesophagus. This is a soft tubular organ which serves to convey food rapidly from the pharynx to the stomach. It extends along the median ventral margin of the neck lying dorsal to or to one side of the trachea. Posteriorly, at the base of the neck and shortly in front of the sternum it broadens slightly and gives rise to a dilated region of the oesophagus, namely the Crop, "whose secretion serves to moisten the food or even to initiate digestion." In larger birds as in the pigeon, the crop appears as an enormous bilobed sac, thus that of the sparrow is often referred to as a degenerated crop since it is merely an enlargement and modification of the oesophagus.

Comments

A Thesis submitted to the Faculty of the College of Liberal Arts or Marquette University in Partial fulfillment or the Requirements for the Degree of Bachelor of Science, Milwaukee, Wisconsin.

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