Five species of Amphihelia are cited by Professor Martin Duncan from the Porcupine' expedition :A. profunda, POURTALES; A. oculata, L. sp.; A. miocenica, SEGUENZA; A. atlantica, n. sp.; and A. ornata,

FIG. 30.-Lophohelia prolifera, PALLAS (sp.). Three-fourths the natural size. (No. 26.)

n. sp.; and on one or two occasions, chiefly on the verge of the cold area, the hempen tangles involved some elegant fragments of the stony coral Allopora oculina, EHRENBERG (Fig. 31).

Although many of the echinoderms of the cold area are common to the warm, the general facies of the echinoderm fauna is different, and there are a number of additional and very striking forms. Cidaris papillata, LESKE, is abundant at moderate

FIG. 31.-Allopora oculina, EHRENBERG.

depths. On our second visit to the Holtenia ground we dredged one small specimen of the handsome urchin already described, Porocidaris purpurata. A fine brilliantly-coloured urchin of the Echinus

flemingii group, but distinguished from E. flemingii by characters which I must regard as of specific value, Echinus microstoma, WYVILLE THOMSON, was common and of large size; and along with it many very beautiful brightly-coloured examples of the smallest form of E. norvegicus.

The three species of the Echinothuridæ, Calveria hystrix, C. fenestrata, and Phormosoma placenta have as yet been met with in this region only, and they seem to have a wide distribution, stretching at about the same depth and temperature from the Faroe Islands to the south of Spain. I hear from Professor Alexander Agassiz that Count Pourtales has dredged fragments of one of the species under nearly similar circumstances in the Strait of Florida. Cribrella sanguinolenta was in thousands, of all colours-scarlet, bright orange, and chocolate brown. Several examples were found of a fine Scytaster, probably identical with the Asterias canariensis of D'Orbigny, and if so having a southern distribution. The curious little Pedicellaster typicus of Sars was not unfrequent; a form which looks very much like the young of something else. One small specimen of Pteraster militaris came up from the Holtenia ground, but with the exception of Astropecten tenuispinus, which seemed to be more abundant than ever, the characteristic arctic echinoderms were absent. We took no examples here of Toxopneustes drobachiensis, Tripylus fragilis, Archaster andromeda, Ctenodiscus crispatus, Astropecten arcticus, Euryale linkii, Ophioscolex glacialis, or Antedon escrichtii. It is very likely that there may be colonies in the warm area' of some or of all of

these for the region in which they are common under very different climatal conditions is within a few miles, and there is no intervening barrier—but

FIG. 32.-Ophiomusium lymani, WYVILLE THOMSON. Dorsal surface; natural size. (No. 45.

they certainly are not abundant. Amphiura abyssicola, SARS, was in great numbers sticking to the sponges, and Ophiacantha spinulosa was nearly as common as in the cold area.

We took one or two small examples of a very fine ophiurid, of which larger specimens had been previously found at about the same depth and temperature during the second cruise of the same season off the coast of Ireland. This form probably ought to be referred to Lyman's genus Ophiomusium,

FIG. 33.-Ophiomusium lymani, WYVILLE THOMSON. Oral surface.

though the characters of the genus must be somewhat altered to admit it. Ophiomusium eburneum, LYMAN, of which several specimens were taken by Count Pourtales at depths of from 270 to 335 fathoms, off Sandy Key, is distinguished by the great solidity and complete calcification of the