QEIfEBA AND GROTJPS OF THE ECHINOIDEA. 167 



I. Siibfamilj IJchinocoitincB. 

 Tall, conical or subhemispherical testa, rather flat actinally ; 

 the peristome more or less symmetrical ; ambulacra with triplets 

 ©f pairs of pores actiually ; periproct submarginal or marginal. 



Genus Eehinoconus. 

 Lanieria. 



Genus EcHiK"OCOE-DS, Breyuius, 1732, Schediasma de EcJi. p. 57, 

 pi. 3. fig. 12. Besor, 1842, Monogr. d'Ech. viv. etfoss. livr. 3, 

 p. 7. E. Forbes, 1850, Mem. Geol. Surv. decad. iii. pL viii. 

 Cotteau Sf Triger, 1S59, Ech. de la Sarthe, p. 279. Loven, 

 1872, Etudes, pi. xv. Martin Duncan, 1881, 0-eol. Mag, 

 p. 10. Loven, 1887, E'lhang till Kongl. SvensTc. Vet.-ATcad. 

 Handl. Bd, 13, Afd. iv. no. 10 (Stockholm, 1888), p. 10. 

 Euncan Sf Sladen, 1889, A?in. ^ Mag. Nat. Hist. ser. 6, 

 vol. iv. p. 238. 

 Syn. Galerites, Lmk. 1816, Anira. s. Vert. vol. iii. p. 20 ; 

 Desor, 1842. Gonulus, Klein. 



Test moderate, thin ; oval, circular, or subpolygonal in mar- 

 ginal outline ; tall, conical, subconical, or tumid, and subhemi- 

 spherical dorsally, flat or slightly tumid actinally. 



Apical system small, compact, with four basal plates which are 

 perforated ; the madreporite in the right anterior, the bas ils 1 

 and 4 in contact and. behind the madreporite, or slightly separated 

 by one or by both of the posterior radial plates ; antero-lateral 

 radial plates separating the basal plates or not. 



Ambulacra flush, or slightly raised, apetalous, straight; plates 

 both low primaries and demi-plates, with larger primaries, some 

 compound plates ; pairs of pores small, in simple series abactia- 

 ally and in oblique triplets actinally and close to the peristome. 

 Interradia with a modera,te number of broad, not very high plates. 

 Ornamentation of numerous small primary tubercles, and 

 an epistroma of scattered distant sharpish granules. 



Peristome central, sunken, slightly decagonal, symmetrical ; 

 some interradial marginal regions with one plate only ; with an 

 ascending, slightly developed tube ; ten small, thick, buccal 

 plates close to the margin. Perigiiathic girdle reduced to a 

 thickening of the interradia as a low false ridge. Jaws none. 

 Periproct marginal or submarginal. 



Fossil. Cretaceous : England, Europe, N. Africa, Asia. 



