508^ 



REVISION OF THE AXINELLID^, 11., 



differ from the styli only in being curved symmetrically and 

 more strongly, and also somewhat angulately. In different 

 specimens, the megascleres vary from 520 to 670/x in maximum 



length and from 16 to 22/u. 

 in maximum stoutness; and 

 the shortest spicules in any 

 specimen are between 200 

 and 300//, in length. The 

 longest spicules are seldom 

 much more than one-half 

 (very rarely, if ever, as 

 much as two-thirds) the 

 maximum stoutness, the 

 greatest diameter being at- 

 tained by those of inter- 

 mediate and lesser lengths, 

 (ii.) The sigmata are, 

 almost without exception, 

 more or less contort, but 

 seldom to such an extent 

 as to appear J-shaped when 

 viewed from the side. I hey 

 are of two sizes, the larger 

 15 to 21/ji, the smaller 7 to 

 11/x, in length, and mea- 

 sure respectively 1'5 and 

 about 0'75/A in maximum 

 stoutness. The latter are 

 by far the less numerous, 

 but are nevertheless by no 

 means scarce. 



(iii.) The trichites are 

 typically of two sizes; the 

 longer ones immeasurably 

 thin, 50 to 65/i. in length in some specimens, only 35 to 50/a in 

 others, and occurring both in dragmata and scattered singly; the 

 shorter ones relatively stouter and slightly fusiform in shape, 



Text-tig. lU. 

 Allantophora pUcata. a, megascleres; li, c, 

 larger and smaller sigmata; rl, e, miero- 

 strongyla from each of two different 

 specimens. 



