398 THE VOYAGE OF H.M.S. CHALLENGER. 



Species 3. Clionclasma dceclerlei7m, n. sp. 



A slightly undulating upright plate, with irregular rounded margin and somewhat 

 thickened firmly attached basis. The dictyonal framework agrees essentially with that 

 of Clionclasma lamella. The parenchyma contains, besides the uncinates, numerous large, 

 delicate discohexasters, with short principal rays on each of which three or four long, 

 thin, somewhat curved or undulating terminals are borne. The dermal and gastral 

 skeletons consist of hexaets with bushy, freely projecting radial ray, and of scopulae with 

 four straight or slightly curved prongs, covered with short barbs, and ending either in 

 simply rounded, or in small knob-like extremities. Japan, 80 to 200 fathoms. 



Species 4. Chonelasma calyx, n. sp. 



The body is cup-shaped, and over a hand's length in height. The dictyonal frame- 

 worK of the cup and of the radial glove-finger-like parietal diverticula consists of smooth 

 or slightly spinose beams, and is slightly more irregular than that of Chonelasma lamella. 

 The loose parenchymalia resemble those of the latter. In the dermal and gastral hexaets 

 the freely projecting ray is somewhat compressed and clubbed, and is further beset with 

 scale-like lateral teeth. The dermal and gastral scopiilse bear four to six straight or 

 S-shaped prongs, beset with barbs, and either rounded off at the ends or with a club- 

 shaped thickening. Japan, 80 to 200 fathoms. 



Family IV. T r e t o d i c t y i d ^, F. E. S. 



Uucinataria with irregular afferent and efferent canals which penetrate the body- 

 wall, not at right angles to the bounding surfaces, that is transversely, but obliquely or 

 longitudinally, or even in curved course. 



Genus 1. Hexactinella, Carter. 



Cup- or tube-shaped forms, with canals which traverse the body-wall in an oblique 

 longitudinal dii-ection. The dictj'onal framework contains reticulate plates, extending 

 between parallel canalicular spaces in a longitudinal or radial fashion. 



Species 1. Hexactinella tuhulosa, n. sp. 



Dichotomous and anastomosing tubes as thick as a little finger, rising from an 

 encrusting base, and opening terminally by terminal apertures. The beams of the 

 dictyonal framework are tubercled, and united without thickened nodes. 



