76 I. IJDIA : HEXACÏINELLIDA. I. 



margin of which arose a numher of short, and uniformly exceedingly 

 fine terminals in a single whorl. The terminals measured scarcely 

 over 10/^ in length and together formed a wine-glass-like perianth 

 (fig. 10). I have failed to discover a still younger stage, much 

 as I have wished to do so ; so tliat, the mode of development of 

 the principals must ever remain entirely in the dark. On the 

 other hand, I have succeeded in ohserving a continuous gradation- 

 al series of forms leading from the above-described stage up to 

 the completely developed floricome. The fine terminals elongate 

 and by flaring out at the outer end convert the perianth into a 

 deep bell-like shape (sigmatocome, fig. 11). (See p. 52). The 

 outer portion of the terminals has somewhat thickened, but the 

 extreme tip appears still pointed (fig. 14a). It continues to thicken 

 especially at the tip ; meanwhile, the latter passes into a state 

 which, when observed under a high power, appears as obliquely 

 and somewhat roundly truncated (fig. 12; fig. 14*^). It may now 

 show small rudiments of the marginal teeth (fig. 14c) and indis- 

 putably presents itself as an inceptional terminal plate of the 

 floricome. Fig. 14 d represents a fully developed terminal in the 

 same scale of magnification as the developmental stages a, b, and 

 c of the same figure. 



In E. aspera, F. E. Schulze ('95, p. 29) found the terminals 

 of young floricomes with a knob-like swelling at the free end. 

 In E. wiperialis and E. marshalli, this is never exactly knob- 

 like but rather obliquely truncated as already mentioned. 



The oxj/hexasters (fig. 15) measure 83-92 /i, mostly about 86/^, 

 in diameter. They are by far less numerous than the floricomes. 

 While in some places in the deeper parts several oxyhexasters 

 were found together at no great distances from one another, they 



