324 THE DOLABELLINAE. 



tively small, much less than Tethys in its proportionate dimensions. The 

 second, or triturating stomach Ues upon the left anterior face of the posterior 

 visceral mass, its long axis being directed downward, inward, and forward, and 

 opening into the large saccular third gastric division. The second stomach 

 has a thick gUstening yellowish muscular wall, and is cylindrical in form, measur- 

 ing 14.0 mm. in length by 22.0 mm. in diameter. Upon its inner surface are 

 borne several rows of large strong horny teeth, which nearly close the lumen 

 as they meet in the centre. They are readily detached from the plate-Uke eleva- 

 tions of the wall bearing them. Plate 10, fig. 1 illustrates in an outhne drawing 

 the relative size and position of these areas, the stomach having been sUt length- 

 wise and opened out flat, and the teeth being all removed; a is the posterior 

 end of the oesophagus, h, the ingluvies, or first stomach, c the thick-walled second 

 stomach, and d, the roomy third division. 



The largest teeth of this first grinding stomach are of a dark amber color 

 and have the approximate form of a four-sided pyramid, the very convex base 

 rhomboidal in outUne, the sides somewhat concave, and the blunt irregular apex 

 almost directly above the middle of the base (Plate 10, fig. 5). These largest 

 teeth reach a height of 10.5 mm. with basal dimensions nearly the same, and 

 are borne in a circle midway of the organ. 



Behind these and alternating with them is a single row of medium sized 

 teeth and in front of them two more rows, the nearest of mediimi size, the 

 most anterior quite small. The teeth of medium size are of the same color 

 and shape as the largest ones, though often more compressed laterally (Plate 10, 

 fig. 2, a and 6, fig. 8, 10). About nine teeth make up this group, and they 

 pass over into that of the smaller size, in which the tooth is strongly compressed 

 and becomes somewhat wedge-shaped (Plate 10, fig. 4, a and h). The tallest 

 central part of such a tooth is occupied by a sUghtly curved axial portion of a 

 fighter color, in which the parallel fines of growth are strongly marked. This 

 flattened shaft extends upward from the middle of the base and forms the cusp 

 of the tooth at its apex, and appears as if imbedded in the remainder of the 

 chitin, especially when viewed as a transparent object. The basal length of 

 the largest tooth of this type is 6.0 mm., its height 6.5 mm. and its width 4.0 mm. 



The smaUest teeth form a fourth type in shape, that of a slender conical 

 spine, (Plate 10, fig. 3). Several of these are found in the anterior row of the 

 second triturating stomach, but they are more characteristic of the third gastric 

 division (Plate 10, fig. \,d). Here they are smaller (Plate 10, fig. 6), and very 

 abundant, being scattered closely over the whole inner lining. Each of these 



