BREYNIUS' GENERA. 191 



was changed into Cidaris by Klein, in 1734, into Echiiiushy Linnseus, in 1758, and into 

 Echinus and Cidaris by Lamarck in 1801, who suppressed the name Echinometra 

 altogether. It has been restored to another group of Urchins by Agassiz in 1846, 

 who unfortunately attributed the name to Klein instead of Breynius its author. 



II. Gemis — EcHiNOCONUs, Breynius, 1732. 



The mouth in the centre of the base, and the vent beneath, at the margin, or above 

 the border ; the shell elevated, round, or conoidal. This generic name was ignored by 

 Klein, 1734, who changed it to Conulus ; Leske, his commentator in 1778, changed it to 

 EcMnites. Lamarck, 1801, omitted the names proposed by his predecessors, and gave 

 that of Galerites to the same group; all the authors down to the time of Alcide 

 d'Orbigny have followed Lamarck instead of Breynius, who nearly a century before 

 had well described and figured this genus. 



III. Genus — Echinocorys, Breynius, 1732. 



* 



The test is helmet-shaped, with the mouth and vent beneath, the former aperture 

 before, and the latter at the marginal border. This generic name was ignored by Klein and 

 changed by him to Galea in 1734. It was retained by Leske, 1778, by Parkinson, 1811, 

 and Mantell, 1832. Lamarck in 1801 proposed the new name Ananchytes for this group, 

 which was retained and adopted by all subsequent modern authors down to 1853, when 

 d'Orbigny restored to this form Breynius' original name Echinocorys. 



IV. Gettus — EcHiNANTHDs, Breyuius, 1732. 



Large, oblong, shield-shaped Urchins with petaloidal, ambulacral areas , the mouth- 

 opening beneath near the centre, and the vent within or below the marginal border ; this 

 genus was preserved by Gaultieri, 1742, and Leske, 1778. It was changed into Scutum 

 by Klein, 1734; into Clypeaster by Lamarck, 1816; and into Echinolamjjas by Gray in 

 1834. Agassiz and most other modern authors retained the name Echinolampas until 

 d'Orbigny rightly restored the old original name Echinanthiis to all oblong Urchins with 

 leaf-shaped ambulacra and the vent in the lower border. 



