CORALS OF THE LONDON CLAY. 25 



3. Paracyathus brevis, Tab. IV, figs. 3, 3 a, 3 b, 3 c. 



Paracyathus beevis, Milne Edwards and J. Haime. Ann. des Scien. Nat., 3 me serie, 

 vol. ix, p. 32.3, 1848. 



The fossil remains of this species which we have had an opportunity of examining, are 

 all more or less imperfect, and could not give us a complete knowledge of its character, 

 but are sufficient to show that it belongs to the genus Paracyathus, and differs from all 

 the other species of the same group. The general form of the corallum appears to be 

 usually subturbinate and short (as in fig. 3) ; but if, as we have some reason to think, the 

 natural interior cast represented in fig. 3 c belongs to this species, the proportions of 

 height and breadth must be very variable. The costa are closely set, nearly equal, thick, 

 and covered with dense granulations. The calice is circular, and the fossula deep. The 

 columella is concave, large, and delicately papillose. The septa are but very slightly exsert, 

 closely set, thin towards the centre, and very thick towards the outer edge, strongly 

 granulated laterally, and almost equally developed. The pali correspond to the septa of 

 the first three cycla, and are very thin, lobulated, and, as usual, developed in an inverse 

 ratio with the septa, in the prolongation of which they are placed. Height, from four to 

 seven lines ; diameter of the calice, six lines; depth of the fossula, one line and a half. 



The existence of only four cycla of septa distinguishes this species from Paracyathus 

 Stokesii, P. Desnoyersii, and P. procumbens, in which there are five of these cycla ; the 

 tenuity of the pali distinguishes it from P. aquilamellosus, P. Pedemontanus, P. Turonensis, 

 and P. crassus ; it is nearest allied to P. caryophyllus, in which the pali are also very thin, 

 and lobulated, but in the latter the septa are much thinner, and the general form is very 

 different. 



Paracyathus brevis is found at the Isle of Sheppy, and the specimens figured in this 

 Mooograph belong to the cabinet of Mr. Bowerbank. 



Aberrant Group or the PSEUDOTURBINOLLDtE (p. xix). 



Genus Dasmia (p. xix). 



Dasmia Sowerbyi. Tab. IV, figs. 4, 4 a, 4 b. 



Desmophylixsi, J. Decarle Sowerby. Trans of the Geol. Soc. of London, vol. v, p. 136', 



tab. viii, fig. 1, 1834. 

 Dasmia Soweebyi, Milne Edwards and /. Haime. Ann. des Sc. Nat., 3 me serie, vol. ix, 

 p. 329, tab. vii, figs. 8, 8 a, 1848. 



Corallum subturbinate, straight, or slightly curved, and subpedicellate or adherent by 

 a very narrow basis. Costa extremely broad, separated by deep, narrow furrows, obtuse 



4 



