TEBKNNOPHORUS. 181 



pi'rfi'ct laterals. Tlic central teeth have a very lon^ narrow base of attachment 

 wiiK'uing towards the lower margin, whi<;h is excavateth There is a line of rc- 

 inforecment running parallel to tlic lower edge, and for a short distance along 

 (he sides. The rerteetA'd j)()r(ion ecpials only one fourtli of the l<'ngth of the 

 base of attachment. It is stout, and hears a short, stout, nutdian (tusp, having a 

 bhitrt, blunt cutting point. There arc no side cusps or cutting points. 



The laterals are like the centrals, but asymmetrical ; their reflected por- 

 tion is also longer. The outer laterals 6 have an outer side cusp. 



The marginals c are a simple modification of the lat<'rals, being qtiadratc, 

 longer than wide, with one inner broad, long, oblicjue, bluntly pointed cutting 

 point, bearing an inner, side, short, acute cutting point. These cutting points 

 on the extreme marginals d are simply short and bluntly rounded. 



Some membranes examined by me seemed to have an extension to the base 

 of attachment beyond the upper margin of the reflected portion, to which it was 

 parallel 



This membrane is peculiar in the long, narrow base of attachment and short 

 reflected portion of the central and first lateral teeth. 



Tebennophorus Caroliniensis, Bo so. 

 Vol. III. PL LXIII. Figs. 1, 2. 



Color of upper surface whitish, or yellowish-white, variegated with clouds 

 and spots of brownish and blackish, so arranged as to form three ill-defined 

 longitudinal bands, one on the centre of the back, and one on each flank, ex- 

 tending from tlie head to the posterior extremity, anastomosing more or less 

 with each other, and having smaller spots of the same color between them ; 

 inferior margin white, or yellowish; foot whitish. Mouth surrounded with a 

 circular row of papilla;. Body elongated, subcylindrical, flattened towards its 

 posterior extremit}', which is obtuse ; eye-peduncles ^ oi an inch long, brownish 

 or blackish, stout, terminating in a bulb ; ocular points on the superior part of 

 the bulb; tentacles immediately below the eye-peduncles, white, very short, 

 nearly conical. Mantle fleshy, covering the whole body, its anterior edge 

 tinged with brownish, and falling in a slight curve between the two eye-pedun- 

 cles, reaching on the sides to the margin of the foot; posterior extremity 

 rounded; cuticle covered with irregular vermiform glands, anastomosino- with 

 each other, and having a general tendency to a longitudinal direction, with 

 shallow furrows between, lubricated with a watery mucus, and susceptible of 

 contractions which produce a slow, undulatory motion, like the flowing of water, 

 over the whole surface. Foot whitish, extending a little beyond the mantle 

 posteriorly, showing a whitish flattened border. Orifice of the organs of gen- 

 eration on the right side, at a Httle distance behind and below the eye-pedun- 

 cles. Respiratory orifice large, on the right side, \ of an inch behind the 

 origin of the eye-peduncle ; anal orifice in close contact, a little above and in 



