Among tlie collections made in the Carribbean Sea and 

 sent liorae to tbe Swedisb State Mnseum twenty vears ago by 

 Dr Axel Goés, Medical Officer at the then Swedish possession 

 St. Barthelemy, tbere was found adhering to the root-filaments 

 of a dried Sponge the test of a minute Echinoid of peeuliar 

 aspect. It bad, unfortunately, long been dead, and was not a 

 little defective, so much so indeed as to make me dubious, 

 not of its general affinities, biit with regard to the propriety of 

 attempting its deseription at a time when living and complete 

 specimens might be expected soon to turn iip from the depths 

 of the Westindian Seas, then subject to most energetic explo- 

 ration. So I simply mentioned its existence, as Py gäster relic- 

 tus ^). The little thing, however, seems to have escaped cap- 

 ture, and now 1 ought not to delay any longer deseribing it, 

 and making out its affinities as far as its defective state permits. 



The dimensions of the specimen are: length 3,5 mm.; 

 breadth 0,41 mm.; hcight 2,i6 mm. The ambitus, Pl. 1, fig- 

 1, 2, is sub-pentagonal, the ambulacra forming the five obtuse 

 ano-les, the interradia the faintlv convex sides. The breadth 

 is 0,9 7 of the length. The height is great in proportion, being 

 0,6 2 of the length. The forepart is somewhat higher than the 

 hind part. The flanks are rounded. On the moderately con- 

 vex nnderside the stoma, slightly entering, is central and cir- 

 cnlar; its diameter is 0,2 9 of the total length. 



On the dorsal side the test has been broken, and impor- 

 tant parts are löst, but it appears that the place of the caly- 

 cinal system has been opposite to the stoma, and the periproct 

 posterior. 



The peristome, /7V/. 4, ö, is made up of the five ambu- 

 lacra and the five interradia. The sntures of the plates are 

 to be distinguished only when seen from the interiör, /?<;. 2, 5. 



') Études sur \es Echinoidées, p. 79, note. 



