590 MR J. W. GREGORY ON THE MALTESE FOSSIL ECHINOIDEA. 



Family ECHINIDJE. 



Genus Echinus, Linn., 1758. 



Species l. Echinus duciei, Wright, 1855. 



Synonymy — 



Echinus duciei, T.Wright, 1855, " Foss. Echinod. Malta," Ann. Mag. Nat. Hist. (2), xv. p. 109, 



pi. iv. f. 2, a-f. 

 Psammechinus duciei, Desor, 1856, Syn. £ch. foss., p. 121. 



„ ,, T. "Wright, 1864, "Foss. Echinidse Malta," Quart. Journ. Geol. Soc, xx. 



p. 475. 

 ,, ,, G. Seguenza, 1869, "Posiz. stratig. Cly. alius," Atti Soc. licit Sci. Nat., xii. 



p. 658. 

 „ ,, G. Laube, 1871, "Ech. oesterr.-uug. ober. tert. Ablag.," Abh. k. 1c. geol. Reichs, 



v. p. 59. 



Type. — Coll. Earl of Ducie. 



Distribution. — Malta — Upper Coralline Limestone ; Garschenthal (second Mediter- 

 ranean stage, Tortonian). Italy — Pianosa (Tortonian). 



Remarks. — In a note by Dr Leith Adams, quoted in Dr Wright's second paper, the 

 absence of this species in the Globigerina Limestone is remarked, and it is recorded in 

 abundance from the Lower Coralline Limestone ; these latter specimens, however, belong 

 to a new species, E. tongrianus. 



Species 2. Echinus tortonicus, n. sp. Plate I. fig. 5a-d. 



Diagnosis. — Small, circular, very depressed. 



Apical disc small ; large antero-lateral basals, with a well-marked madreporite on 

 that of the right side. The posterior basals are small. The postero-lateral radials enter 

 the anal ring. One granule on each basal. 



Ambulacra : A pair of rows of tubercles in each area ; primary tubercles smaller than 

 those of the interradii. A good number of coarse granules down the middle of each area. 



Interradii : A vertical row of large primary tubercles down the adambulacral side of 

 each series of plates. Each primary tubercle is surrounded by a circle of granules 

 composed of a horse-shoe-shaped line on the one plate, completed to a circle by a few 

 granules on the lower plate. At the ambitus a large secondary tubercle appears on the 

 inner side of each plate, while a small secondary is developed on the adambulacral side ; 

 the latter may be replaced by two coarse granules placed one above the other. The 

 granules are coarse, but sparse. 



Dimensions. — Diameter, 20 mm. ; height, 6 mm. Ambulacra, width at ambitus, 

 4'5 mm. Interradii, width at ambitus, 7 mm. 



Distribution. — Malta — Upper Coralline Limestone (bed c). 



Type.—hv\t. Mus., E. 3402. 



