304 s. CK)TO : 



of different lengths, but mostly mncli longer than the first pedicella- 

 ria. On the outer part of the month-plate there are some 5-10 

 small spines. 



Ventrolaterals. — There is a single series of small ventro- 

 laterals extending throughout the length of the arms. In the 

 proximal half of the arms each plate bears a few small spines 

 and frequently one forcipiform pedicellaria, similar in form and 

 size to those of the inferomarginals. Further out in the arms the 

 ventrolaterals are entirely naked, so that the adambulacral and 

 the inferom.arginal plates appear in this part separated by a longi- 

 tudinal space. The ventrolaterals are strictly coincident with 

 the adambulacrals and inferomarginals. 



Paxillœ. — The paxilla? at the centre of the disk and along 

 the middle of the arms are smaller than the others (PI. VI, fig. 

 95). On either side of the arm, next to the inferomarginals, 

 there are usually three longitudinal series of paxillae, almost 

 square in form and larger than the rest, mostly bearing a con- 

 spicuously large conical spine at the centre of the tabulum (PI. 

 VI, fig. 103). In the series immediately adjoining the infero- 

 marginals the central spine is particularly large, being nearly one- 

 third as long as the marginal spine of the inferomarginals, and 

 is surrounded by some five or seven much smaller, short spines 

 and 1-3 small pedicellarise (PI. VI, fig. 102) ; the latter may, however, 

 be entirely absent on some of the plates. The peripheral spine- 

 lets are ciliary and are arranged in an irregularly double row 

 along the margin of the tabnlum. The paxillae of the second 

 row are smaller than those of the first, there being three or four 

 of them to every two of the latter ; the central spine is much 

 smaller, and may often be absent, in which case there are some 



