192 PEOP. p. M. duncak's eeyisiok op the 



De Loriol established the genus PTiylloclypeus in Mem. Soc. de 

 Phys. at d'Hist. ISTat. de G-eneve, 1880, vol. xxvii. p. 79. 



The question arises, What is the difference between Gono- 

 lampas, Agass., and. Phylloclypeus, De Loriol? I cannot see 

 that there is much structural difference of physiological import- 

 ance, between them. The question is complicated by De Loriol's 

 decision tbat G. Sigsbei, A. Agass., " est certainement un EcJiino- 

 lampas" Cat. Eais. des Ech. rec. a I'lle Maurice, Mem. Soc. Phys. 

 et Hist. Nat. de G-eneve, vol. xxviii. p. 44 (1883). My study of 

 the great series of Echinolampas in tbe Tertiaries of W. Sind. 

 clearly decides in my mind the classificatory importance of the 

 unequal poriferous zones in the same ambulacrum ; and I cannot 

 admit in the typical genus Tlcliinolampas forms with, equal, long 

 or short ambulacral zones. I demur, therefore, to the opinion 

 of my friend, that Gonolampas is an Echinolampad. I am 

 content to believe that the two genera will come within the same 

 alliance as Palceolampas, Bell, and Microlampas, Cotteau. 



G-enus Phtllooltpeiis, Be Loriol, 1880, op. cit. p. 79. 



Syn. ? Glypeolampas, Pomel, 1868, j^^e Pomel. 



Test large, Conoclypeoid in shape and structure, except that 

 there is neither a perignatbic girdle nor jaws present. On the 

 other hand, the floscelle is well developed and there are accessory 

 plates in the phyllodes. Periproct oval, longitudinal, sub- 

 marginal. 



Fossil. Upper Cretaceous, Jlde Cotteau : Europe. Eocene : 

 Europe, Africa, Asia. 



G-enus Gonolampas, A. Agassiz, 1883, 'Blake' Bch., Mem. Mus. 

 Gonip. Zool. Sarv. vol. x. no. 1, p. 48, and 1888, vol. xv. p. 99 

 {non Gonolampas, Pomel, 1883). 



Syn. Gonoclypeus, A. Ag. (non auct.), 1878, Bull. Mus. Oomp. 

 Zool. no. 9, p. 190, pis. 1, 2. 



Test large, taller than broad, hemispherical above the almost 

 circular margin ', flat actinally. 



Apical system small, projecting at the centrally placed apex ; 

 button-shaped ; four basal plates perforated ; the madreporite in 

 the right anterior basal, and extending into tbe centre of the 

 system, and separating the basals; five radial plates, small, 

 and the postero-lateral in contact witb the madreporite and 

 separated by it. 



