OCR Text |
Show 680 PROF. A. H. G A R R O D O N [June 18, tact, being situated laterally upon opposite sides of the gullet. These areas are flat, except at their upper margins, where a small transverse ridge is developed, which may be the slight foreshadowing of the special cavity developed in Plotus anhinga for the reception of the secretion of the gastric glands. But in P. levaillanti it is to be noticed that there are two gland-surfaces, whilst in P. anhinga it will be remembered there is but one gland-cavity. View of the inner surface of the posterior wall of the stomach of Plotus levaillanti, witli the oesophagus slit up anteriorly so as to show the whole of its proventricular surface, with the two gland-areas and the TJ-shaped elevation on its anterior wall (on the left of the figure), as well as the pyloric infundibuliform plug. The calibre of the oesophagus must be somewhat diminished by the presence of a curious U-shaped ridge upon the mucous membrane of its anterior wall, which is situated between the anterolateral margins of the gland-areas, and has a small pit in the part |