SPHEXOTROCHUS AURITUS. 37 



S3'stems remains permanently attached to the new individual. Height 6 or 

 7 mm., diameter 3 mm. 



Barbados, 100 fathoms ; not rare. 



THECOCYATHUS M.-Edw. & H. 

 Thecocyathus cylindraceus Potjrt. 



Off Barbados in 100 fathoms one specimen only was obtained. A dead 

 specimen of a Thecocyathus, probably of that species, was dredged in 3-3 

 fathoms off Cape Frio, Brazil. 



SPHENOTROCHUS M.-Edw. & H. 



Sphenotrockus auritus ». sr. 



PI. VI. frjs. u, is. 



Corallum wedge-shaped, with broad and thin base, having in the middle a 

 small knob containing a grain of sand, and on each side a flat protuberance 

 somewhat resembling that of Platytrochus, pointing downward, so that the 

 base has a three-pointed appearance in perfectly formed specimens. In old 

 specimens the outline becomes more irregular. The costa> radiate on the 

 sides from the central protuberance in the shape of a fan ; they are formed 

 by rows of flat tubercles or interrupted ridges, at first simple, then double, 

 and finally treble or even quadruple near the calicle, ending by giving the 

 outer edge of the septa a very crispate appearance. The angles of the base 

 are covered with similar tubercles or granules irregularly arranged or form- 

 ing obscure lines diverging from the costa\ Septa thick, with frilled edges 

 and thickly covered with sharp granules, in six systems of three cycles. The 

 lamellar columella is granulated like the septa. Height mm., breadth of base 

 4-5 mm., greater diameter of calicle 7-8 mm., smaller diameter -4 mm. 



Several specimens, all dead, but perfect, were obtained oft' Cape Frio, Brazil, 

 in 35 fathoms, sandy bottom. 



A few specimens of a Sphenotrochus were dredged in 12 - IS fathoms on 

 the coast of Brazil in lat. II 3 49' S. which may belong to another species, or 

 be the young of the above. They are much smaller, regularly conical and 

 flattened, but without lateral expansions, and the costie are formed of flat 

 pavement-like tubercles. They are all somewhat worn. 



