ORCELLA. 375 



somewhat to meet the oesophagus, the posterior wall of which is in the same plane 

 with the dorsal wall of this cavity. The sac is much longer from left to right 

 than it is broad antero-posteriorly, and it is placed transversely across the body. 

 When the oesophagus is laid open posteriorly, one of the folds of that tube is 

 observed to become enormously enlarged into a free flap which depends behind the 

 opening into the second stomach so as completely to prevent the entrance of food 

 into it, on its passage down the oesophagus. The entrance to the second cavity 

 occurs at the angle formed by the oesoj)hagus and the cavity in question, and is 

 directed upwards and forwards, and towards the left side. The walls of the cavity 

 are of great thickness. The mucous membrane is very rough and yellow, and 

 covered all over with small, short, much convoluted ridges, with deep intervening 

 sulci ; the whole surface, in addition, being thrown into enormous folds which are 

 arranged around the opening into the second cavity so as to close it completely. 



The second stomach (fig. 5, ii.) has only about one-half the capacity of the first. 

 It lies above and over the right third of the previous cavity at right angles to its long 

 axis, its base being dorsal or at the oesophagus, and its apex oj)posite to that, on the 

 ventral wall. It is oval in form, with its mucous membrane of a greyish tint and per- 

 fectly smooth, but thrown into large convoluted folds about one inch in thickness and 

 diameter, and which radiate from the communication with the first stomach. This 

 opening is placed on a line with the anterior wall of the oesophagus, and when con- 

 tracted has a length of two inches. The rough yellow mucous membrane of the first 

 stomach is visible around the opening common to the two cavities when the second is 

 cut open. The orifice leading to the third stomach occurs about one inch below the 

 last mentioned opening and it looks backwards. It is a narrow sht one-fifth of an 

 inch in breadth, and the mucous membrane immediately around it is not convoluted- 

 On laying the channel open it is found to dilate suddenly into a tube about half an 

 inch in diameter, but at its lower thhd it expands even to about twice that dimen- 

 sion, again contractiug to half an inch at its orifice leading to the third stomach. 

 The third stomach (fig. 5, iii.) Hes below the opening from the second stomach, 

 being distant from it about two iuches, viz., the length of the channel between 

 these two cavities. 



It assumes the form of a tube bent upon itself, and the convexity of the bend 

 which is directed anteriorly is on a level with the upper opening of the funnel-Hke 

 passage leading into it from the second stomach, while its left side lies parallel 

 mth the same passage. The pyloric orifice is on a level with the lower third 

 of the first stomach, and about an inch below the base of the sacculation 

 which marks the beginning of tliis cavity. There are some obscm-e folds in the 

 latter locality, and a few similar folds at the bend. The mucous membrane is 

 whitish, and presents two distinct characters. In the greater part of its extent it 

 is covered with a fine mesh work of more or less transverse fibres enclosing shallow 

 depressions or pits, with a few isolated funnel-hke orifices thus resembling the 

 texture of a gravid Cetacean uterus. The remainder of the cavity is quite smooth, 

 but with occasional funnel-shaped openings about 0""04i in diameter. The mucous 



