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



a Latinised form, did not accept it, and Echinorodum therefore dates only from 1883. 

 Both this and Diplothecanthus have therefore to be abandoned in favour of Echinan- 

 thus, and it becomes necessary to propose a new name for the genus of Cassiduloidea, 

 which palaeontologists have long known as such. The name Breynella is therefore 

 proposed for it. 



The following table will show the various uses of the names in question : — 



Leske, 

 1778. 



Lamarck, 

 1816. 



Gray, 



1855. 



Desor, 

 1857. 



A. Agassiz, 

 1872. 



POMEL, 



1883. 



Duncan, 

 1889. 



Gregory, 

 1891. 











/ Clypeaster. 

 \ Echinanthus. 



Clypeaster. 



Clypeaster. 



Clypeaster. 



Echinanthus. 



Clypeaster. 



Echinanthus. 



Clypeaster. 



Echinorodum. 



( Diplothecan- 



< thus. 



( Plesianthus. 



Echinanthus. 

 Plesianthus. 









Echinanthus. 





Echinanthus. 



Echinanthus. 



Breynella. 



Species l. Breynella vasalli (Wright), 1855. 

 Synonymy — 



Pygorhynchus vasalli, T. Wright, 1855, Ann. Mag. Nat. Hist. (2), xv. pp. 271, 272. 



,, ,, ,, 1864, Quart. Journ. Geol. Soc, xx. p. 479, pi. xxii. f. 6. 



Echinanthus „ E. Desor, 1857, Syn. Ech. foss., p. 296. 



„ corsieus, G. Cotteau, 1877, "Faune terfc. Corse," Ann. Soc. Agric. Lyon (4), ix. pp. 288- 



290, pi. xi. f. 1-5. 



Type.— Brit. Mus., E. 1581. 



Distribution. — Malta — Globigerina Limestone. Corsica — Zone a Pecten bonifaciensis. 



Remarks. — Dr Wright having persisted in retaining his species in the genus Pygo- 

 rhynchus, in spite of M. Desor's opinion, it was natural that M. Cotteau should not have 

 been led to compare his Echinanthus corsieus more closely with it. The species agrees 

 very closely with M. Cotteau's careful figures of this species. The absence of the pos- 

 terior rostrum which overhangs the anus in Breynella vasalli would be alone a specific 

 difference between this and Pygorhynchus collombi; and the latter is a true Pygo- 

 rhynchus, so that M. Cotteau's action in making Wright's species a synonym of this 

 cannot be followed. 



Species 2. Breynella equizonata, n. sp. Plate II. figs la-c. 



Diagnosis. — Form oval, flattened posteriorly. Actinal surface flat. The upper 

 surface is regularly rounded. The maximum height is a little behind the apical system. 

 The posterior slope is fairly steep to the low vertical posterior margin. The anterior 

 margin is tumid. The posterior interradius is raised into a blunt rounded ridge. 



Apical system very excentric anteriorly ; four genital pores. 



Ambulacra : Petals short but wide ; closed below. The poriferous zones on the 

 two sides of each paired ambulacrum are of unequal length. The outer pores are wider 



