REPORT ON THE HEXACTINELLIDA. 367 



Species 6. Euplectella crassistellata, u. sp. 



The priucipal parenchymal spicules (priucipalia) arc long smooth oxydiacts with 

 knotted thickening in the centre. The parenchymal oxyhexasters have strikingly thick 

 and somewhat long principal rays, each with four moderately short terminals. Middle 

 of Pacific, 2750 fathoms. 



Species 7. Euplectella (?*) nodosa, n. sp. 



Straight slightly bulging tube (with irregular parietal gaps), without external ridges. 

 The principalia are strong oxypeutacts, in which the distal ray does not project Ijeyoud 

 the external surface. In some dermal oxypentacts the floricome is replaced l^y a tuft of 

 oxydiacts with central iiodes. Instead of the ordinary oxyhexasters, lophohexasters 

 occur. Possibly belonging to the genus Holascus. Bermuda Islands. 



Genus 2. Regadrella, 0. Schmidt. 

 A tubular form firmly attached by means of a knobbed basal portion. 



Species 1. Regadrella phcenix, 0. Schmidt. 



The principalia are large oxy|3entacts, which have their four tangential rays variously 

 disposed in difi"erent directions. Parenchymal discohexasters with short principal and 

 long terminal rays. Antille Islands, 221 to 280 fathoms. 



Subfamily 2. Holascin^. 



Tubular. Without parietal yaps. Without superficially situated floricomes. 

 Parenchymal oxyhexasters. 



Genus 1. Holascus, n. gen. 



With root-tuft and transverse sharply defined terminal sieve-plate. Tlie internal 

 gastral surface bears projecting longitudinal and transverse lattice-work ridges. Hypo- 

 dermalia, sword-shaped hexacts with short rough distal ray, l)esides which ox5'diacts an; 

 radially apposed. 



