348 REPORT ON ALBATROSS MOLLUSC A BALL. 



intestine, in all the specimens, is crammed with a greenish mud, con- 

 sisting of disintegrated foraminifera. 



The dentition recalls that of Calliostoma, Solariella, Margarita, etc., 

 and presents nothing very characteristic. 



The central tooth has a broad thin base, subrectangular, and a little 

 wider at the anterior corners. The stem of the cusp and the cusp are 

 narrow. The latter is simple, rather small, short, and recurved. It is 

 not denticulate. There are three or four admedian or lateral teeth, 

 rather long, with small bases, rather broad, simple, moderately curved 

 brownish cusps. There are about twenty-five uncini, half of which 

 spring from lozenge shaped bases, looking like a pavement ; are long, 

 narrow, slender, moderately curved, with spatuliform tips. One edge 

 of these tips is microscopically serrate, and below the serrate part, on 

 the same side, is a single larger denticle, standing out like a short 

 thumb. 



The external uncini are thin, flat, wide, and hardly curved. Their 

 distal ends are flat and broad, with the e<\^ simple and entire: These 

 teeth gradually diminish in size and width, as usual in TrocMdce. The 

 formula would be 25+3+^+3+25, or very nearly that; but time has 

 been wanting in which to undertake the laborious task of an exact 

 enumeration of these minute aud tangled objects, of which the geueral 

 features have just been recorded. 



; 411 the specimens of Turcicula previously obtained were incomplete 

 and deprived of epidermis. 



The capture of this and the following species, besides adding to our 

 catalogues two of the finest deep sea mollnsks known, has enabled me 

 to fully describe the characters of the group and determine its place in 

 the system of classification. 



Turcicula Macdonaldi sp. uov. 

 Plate vn, Fig. 7. 



Shell very .arge, thin, elevated, with about six whorls, flattened, and 

 appressed above and rounded below. It differs from T. Bairdii in the 

 proportionally narrower cinguli of which only that at the periphery is 

 nodulous, in the more numerous (nine to ten) sharper and more elevated 

 basal cinguli, in the flatter posterior surface of the wnorl aud its being 

 appressed at the suture, in its duller more olivaceous epidermis, more 

 angulated and less reflected outer lip. Although living it was a, good 

 deal eroded, especially at the tip. Altitude of decollate shell, 75 ; max- 

 imum diameter, 60 mm . The operculum has nine whorls, is of the same 

 shape as in the preceding species, but of a darker brown, with a maxi- 

 mum diameter of 29 mm . 



Hab.— Station !i792, off Manta, Ecuador, in 401 fathoms, mud; bot- 

 tom temperature, 43° F. 



The single specimen of this magnificent shell contained the animal, 

 which does not appear to differ materially from the T. Bairdii. It is 



