ACTINOrODOUS HOLOTHUraOIDEA. 



185 



found wheels of 0.068 mm. diame- 

 ter, witli thirteen spokes and five 

 central lioles ; in another specimen 

 were noted wheels of 0.08 mm. di- 

 ameter, with twelve spokes and four 

 central holes. When the various parts 

 of a small wheel are slender, it 

 approaches the wheel-like plate seen 

 in Pannychia. (iii) Eods are found 

 scattered ajjundantly in the ventral 

 perisome in a layer deeper than that 

 of the wheels (r/). Tliey are mostly 

 straight, with some irregular teeth at 

 the ends. Their sizes are anywhere be- 

 tween 0.1 mm. and 0.18 mm. Support- 

 ing rods and end-plates are found oidy 

 in the ventral pedicels. The former are 

 arcuate, with some irregular teeth, 

 about 0.3 mm. or more in length (c). 

 The dorsal perisome, possesses large 

 wheels almost exclusively. Small 

 wheels are few and far between. Tlie 

 ventral perisome encloses both rods and small wheels, which fact 

 constitutes the gi'eat pecuharity of this species. The rods are in 

 a layer deeper than the wheels. Seen in surface view, both are 

 equally abundant. Dorsal papilla3 have almost exclusively small 

 wheels. No supporting rods, nor end-plates. Ventral lateral 

 pedicels have small wheels and supporting rods. Besides these, 

 there are Avell- developed end-plates. The supporting rods are 

 numerous and are present tln-oughout the length of the pedicels. 



Textfig. S3. 

 I.ttimorjonc net/lecta : a — Large 

 wheel of dorsiira ; i— Small wheel 

 of ventnun ; c — Supporting roil ot 

 pedicel ; d — Eoil of \enfml i)eri- 

 aomc. (X '2011). 



