A. E. Verrill — North American Gephalopods. 215 



and the horny ring has a corresponding notch ; the outer or hack 

 portion is much swollen and pi'oduced downward and backward, 

 and here the horny ring is correspondingly broad. The aperture 

 is nearly circular, but is rather shorter from front to back than 

 transversely. In this and some of the other suckers of similar 

 size, the entire circumference of the margin is furnished with rather 

 large sharp denticles which are strongly inclined inward and con- 

 siderably larger on the outer than on the inner margin. There 

 are about thirteen of the large teeth, occupying rather more than 

 half the circiimference ; these are broad at base, bevelled off to 

 an acute edge on the sides, and somewhat acuminate, with sharp 

 tips. Those on the middle of the outer border point inward to 

 the center of the sucker, but those along the sides point rather 

 obliquely to the front margin. The front margin is occupied by 

 about seventeen smaller, unequal, acute, denticles, those in its cen- 

 ter the smallest and most regular; these are acute-triangular and 

 their points are directed more upward than those of the opposite 

 edge. The horny rings are light yellow (when di'ied they are white 

 and osseus), their denticles yellowish white, and often silvery white 

 and lustrous at tip and along their edges, especially when dried. 

 The suckers smaller than the above have fewer of the larger outei- 

 teeth, and usually fewer and less perfectly formed teeth along the 

 front margin. Those that have the aperture 7"'" or less in diameter 

 usually have the front margin of the ring only irregularly fissured, 

 Avith the intervals minutely denticulate or crenulate, while the outer 

 half of the margin may bear nine or ten large and well-developed 

 denticles, with broad stout bases and sharp edges and tip ; the edges 

 of these teeth along the middle are usually convex, and then the 

 outline is incurved to the acute point. One of the smaller suckers 

 examined has the aperture about 4'5'""> in diameter, with the same 

 form as the larger ones ; this has about six large, sharp, denticles, like 

 those above described, on the outer half of the margin of the rings, 

 while the front margin is nearly entire and smooth. The smallest one 

 (J) is similar, with but four distinct, large denticles, with another 

 imperfect, lobe-like one, on one side, and with a smooth front margin. 

 The three largest suckers, (Plate XVII, fig. 9), supposed to be 

 from near the base of the ventral arms, have about 45 marginal 

 denticles, of nearly uniform size, and less incurved than in those 

 above described. In these the back side of the horny ring is less 

 expanded, and therefore the suckers were less oblique than in the 

 smaller ones. The largest of these (a) had the aperture 20""" in 

 diameter. 



