REPOET ON THE HEXACTINELLIDA. 



409 



III. Iljialonehta — continueil. 



The dennnl pinuli have moderately long lateral teeth on 

 the long strongly developed radial ray. The large 

 amphidiscs have eight somewhat broad teeth on the 

 margin of the discs, .... 



12 The small parenchymal o.xyhexacts have oblique in- 



wardly directed lateral spines or barbs on their rays, 

 The rays of the small parenchymal oxyhexacts are quite 

 smooth, ...... 



13 The body has a cup-like or truncated oval form, with 



wide oscular aperture, without distinct sieve- 

 membrane. The large amphidiscs have broad, 

 hemispherical arched terminal discs with only six 

 broad terminally lancet-shaped marginal rays. 



The body is spherical or flat and cake-shaped, with narrow 

 oscular aperture, without distinct sieve-membrane. 

 The large amphidiscs have campanulate terminal 

 discs with eight slender pointed rays, 



14 The larger, though still comparatively small amphidiscs, 



have campanulate terminal discs with eight rather 

 long rays, whose pointed ends reach almost to the 

 middle, ...... 



The larger amphidiscs have an approximately spherical 

 form. The hemispherical terminal umbels exhibit 

 eight to twelve broad terminally rounded marginal 

 rays, which often meet, or alternate with those of 

 the opposite side, ..... 



IV. Numerous radially projecting pleuralia {Pheronema, 



Leidy), ...... 



Without radial pleuralia. External surface smooth 

 {Poliopogon, Wyv. Thomson), 

 V. Pherune)aa, Leidy. 



Body markedly longer than broad, 



Body not longer than broad, .... 



1 Body egg- or pear-shaped, narrowed superiorly. The 



basal tuft consists of several isolated tufts of needles, 



Body resembles a somewhat broad ellipsoid. The broad 

 basal tuft is bushy, .... 



2 Parallel to the cuff-like wreath of marginalia, projecting 



as a fringe round the oscular margin, there is below 

 the oscular margin a connected annular zone of 

 pleuralia, measuring about a finger's breadth, 



(ZOOL. CHALL. EXP. — PART LIII. — 1887.) 



PAGE AND PL.\TE 



Hyalomma ijiwilr, , l 'J6 



XXVII. 



13 

 U 



Hijalonema aperttmi, . 214 



XXXVII., XXXVIII. 



Hyalonema depressum, . 217 

 XXXV., x.xxvi. 



Hyalonema dojaiw, 223 



XXXI. 



Hyahni'ina fenermn, 



V. 

 VI. 



1 



3 



Pheronema annse. 



224 



XXXI. 



239 



XLII. 



Pheronema carpenieri, 241 



XI.III. 



Ggg52 



