( 0NOLA.MPAS SIGSBEI. 51 



resentative of the Conoclypei, with its central apex and characteristic ambu- 

 lacra, l>\ the name Conolampas, until we know more of the structure of the 

 interior of the actinostome of the Cretaceous genus Phylloclypeus of De 

 Loriol, as well as of the species of Echinolampas with high test, to which 

 this species of Conolampas may perhaps lie more closel} related than now 

 appears. Cotteau lias figured such a species of Echinolampas (E. lemwrbis, 

 Guppy) from the Eocene of St. Barthe'lemy, and he likewise calls attention 

 to its resemblance to several species of Conoclypus. 



A.s I have already stated in the Preliminary Report of the Blake Echini 



(Bull. M. ('. 7. . X .. No. '.). ].. I'.tl i. I described in the Revisi ' the Echini, 



ami figured on PI. XVI. of thai work, several stages of the young of Cono- 

 lampas ( Gonoclyjms Sujsbti A. Ag.) a- the young of Echinolampas. I had not 

 at that time dredged Conolampas, and was thus misled, by the examination 

 1 had made of only a lew young stages either of Echinolampas or of Cono- 

 lampas, to consider them all as belonging to the same genus. 



Additional young specimens of Echinolampas and of Conolampas having 

 Keen obtained in the Caribbean by the Blake, 1 am now aide t<> rectify my 

 error, and. by referring to the figures given on Plate XVI. of the Revision, 

 to indicate those which belong to Echinolampas, and those which represenl 

 young stages of Conolampas. 



It will he -een that in corresponding stages of growth of these two genera 

 we find in one case, in young specimens of Echinolampas, already the firsl 

 trace of the peculiar petaloid development of the ambulacra characteristic 

 of this species \ PI. XVI. Figs. 6, 7. i.'ev. Echini); while in the corresponding 

 young stages of Conolampas (PI. XVI. Figs. I. II. I-. Rev. Echini) the 

 ambulacra have the characteristic structure of the genus. To recapitulate. 

 Figs. 6, 7. 17. is. L9, 21, of Plate XVI. of the Revision, belong to Echino- 

 lampas, -while Figs. L-5 and 8-16 of the same plate belong to the young 

 Btagea of < lonolampas. 



The Pygaster or Echinoconus ' stage, if I may so call it. of both Echino- 

 lampas and Conolampas, appears to he a most characteristic stage "f these 



genera, and it i- possible that the recent species mentioned by I. oven as 

 Pygaster reUclus,ma.y after all only be a young stage either of Echinolampas 

 or of Conolampas. This is very probable judging from the size of Love'n's 

 specimen, :; mm. in diameter, and from it- origin, the Virgin Islands. 



he excellent figures of .i fine ncriea of Echinoconus given bj < 'ottenu in Bull Soc. dee Si ien. Hist 

 <t N;.t. de [Tonne, (2,) IV.. 1881, PI. I 



