EEPOKT ON THE SCAPHOPODA. 3 



3. Dentalium amphialum, 1 Watson (PL I. fig. 3). 



Dentalium amphialum, Watson, Prelim. Report, pt. 2, Journ. Linn. Soc. Lond., vol. xiv. p. 510. 



Station 323. February 28, 1876. Lat. 35° 39' S., long. 50° 47' W. Off the mouth 

 of the river Plate. 1900 fathoms. Blue mud. Bottom temperature 33° - l. 



Animal. — Small for the shell, of a pale ruddy colour, which is deeper and browner 

 on the foot and liver, the latter very large : two large masses of long, fiue, equal cap- 

 tacula fill the mantle-cavity ; they spring from the front of the pedestal out of which 

 the buccal mass and the foot rise ; and of these, two large bunches project through the 

 mantle-orifice ; buccal palps very small. 



Shell. — Long, conical, nearly straight, what curve there is very equal throughout, 

 of a dirty brownish-yellow, chalky on the surface, porcellauous beneath. Both specimens 

 are very much eroded, especially on the convex curve, and show a prodigious number 

 of layers of shell, which is, however, thin and slight. There is a short, irregular anal 

 fissure on the convex curve. Sculpture: There are about 50 very slightly raised, rounded, 

 longitudinal ridges, the furrows between which are very much like the ridges reversed, 

 being very shallow and open. These vary a good deal at different parts of the shell, and 

 tend to disappear towards the mouth ; they are crossed by fine, close-set, sharp, but very 

 superficial, irregular scratches, which run elliptically round the shell, advancing on the 

 concave and retreating on the convex curve. As the shell grows, these lines of growth 



~ 0*0 



become harsh and broken. L. 2, nearly. B. 0"3, nearly ; least B. 0"05. 



This species is somewhat like Dentalium zelandieum, Sow., " from New Zealand," British 

 Museum, but in form is much stumpier, the ridges are closer and the shell thinner. Than 

 Dentalium grande, Desh., " Japan," British Museum, it likewise is stumpier in form ; the ridges are 

 le3S strong, the furrows less marked, the circular striae less sharp : in Dentalium amphialum the 

 longitudinal ridges die out, while in Dentalium grande they continue equally strong. 



4. Dentalium keras, 2 Watson (PL I. fig. 4). 



Dentalium ceras, Watson, Prelim. Report, pt. 2, Journ. Linn. Soc. Lond., vol. xiv. p. 510. 



„ „ Dall, "Blake" Exped. Bull. Mus. Comp. Zool. Camb. Mass., vol. ix., p. 37. Station 



33, 1568 fathoms. 



Station 246. July 2, 1875. Lat. 36° 10' N., long. 178° 0' E. Mid-Pacific, E. 

 of Japan. 2050 fathoms. Globigerina ooze. Bottom temperature 35°T. 



Station 299. Dec. 14, 1875. Lat. 33° 31' S., long. 74° 43' W. W. of Valparaiso. 

 2160 fathoms. Blue mud. Bottom temperature 35 c, 2. 



Animal. — Mantle is white, very thin, and transparent ; the adductor muscles are short 

 and weak. The liver is small, of a light greyish-brown. The mouth of the mantle is 

 very strong, of a yellowish colour, and the animal is rather fawn-coloured. 



1 aiJ.<^ia\oc, sea-girt. 2 xhag. a horn. 



