108 Mr, E. A. Smith on Species of 



arrangement of spines on the dorsal surface; but towards the 

 arabulacral furrow there is, first of all, parallel with the spines 

 Avhich border it, a series of very small spines, only one on each 

 plate, so that a narrow bare space is seen ; above this the 

 spines are two or three on a plate. 



Pteraster affinis^ sp. nov.? 



Discus magnus, o-radiatus, inferne planus, supra convexus, medio- 

 criter crassus, latitudine radiorum longitudinem adsequans ; radii 

 breves, ad basim lati, versus extremitates recurvatas sulcos 

 ambiilacrales exponentes rapide angustantes ; eoruiQ superficies 

 infera utrinque membrana tenui spinis circitor 30 graeilibus 

 munita (quarum apices vix extra membranam projiciunt) obtecta ; 

 tessellte interambulacrales spinas quatuor graciles, membrana 

 tenuissima fere ad earum apices extendente connexas gerentes ; 

 oris angulus quisque interradialis spinas 8 similes, membrana 

 pariter connexas gerens, extremis duabus quam caeterae maxime 

 brevioribus, mediauis duabus longissimis ; illas supra sunt spinas 

 duse erassae, altera alterae parallela, medio leviter concavae, longi- 

 tudine spinarum 30 lateralium elongatissimam aequantes, et versus 

 apices leviter acuminatae ; superficies dorsalis et laterales pro- 

 jecturis minimis spiuiferis munitaj, et inter has pons minutis 

 baud numerosis perforatae ; spinas supra projecturas scabrae 4-10, 

 membrana praster ad apices amictae ; foramen centrale mediocre, 

 circulare, lacinia spinarum brevium membrana connexarum cir- 

 cumdatum. 



ExemjDli maximi disci diam. 15 millim., crass. 7 ; radiorum longit. 17, 

 diam. ad basim 8. Exempli minoris disci diam. 10 millim., 

 erass. 5, radiorum longit. 9, 



This species approaches very closely to Pt. Dance of Verrill, 

 described in the ' Proceedings ' of the Boston Society of Natural 

 History, 1869, vol. vii. pp. 386 & 387, and which is supposed 

 to have been found at Rio Janeiro. It appears, however, to 

 be provided with longer arms ; the spines of the dorsal fascicles 

 are everywhere similar and scabrous ; the spines at the inter- 

 radial corners of the mouth are only eight in number ; and the 

 two larger spines above them are not very long, but stout. In 

 these respects it chiefly differs from Pt. Dance. The smaller spe- 

 cimen, it will be noticed, is considerably shorter in the rays. 



Porania antarctica^ sp. nov. 



Discus 5-radiatus, medioeriter crassus, latitudine radiorum longitu- 

 dinem aequans ; superficies infera omnino plana, supera convexa ; 

 radii aliquantobreviter couici, versus apicem aeumiuati; totum ani- 

 mal cute crassa carnosa amictum, inferne a marginibus ad sulcos 

 ambulacrales lineariter radiatim sulcata, superne laevi spinis paucis 

 tubcrcularibus parvis prope medium supraque radios sparsim or- 



