Bd VI: 4) 



THE ECHINOIDEA. 



93 



— In the type specimen all the paired interambulacra are excluded from the peri- 

 stome, as shown in the figure quoted (PI. V. 37); in the present specimen this is 

 the case with interambulacrum 1., not with 2.; those of the other side I have not 

 denuded, so I cannot state how it is with them. — The spines of the plastron were 

 all broken, so that I cannot, any more than KOEHLER, give definite information of 

 their shape; judging from some spines preserved in most of their length, the point 

 is probably only slightly widened. 



KOEHEER has pointed out the most interest- 

 ing feature that the odd anterior ambulacrum is 

 of almost the same shape as the paired petals, 

 and that the pores are developed in the same 

 way in all of them. It is in accordance with 

 this fact that the tubefeet are also developed in 

 the same way; the abactinal tubefeet of the an- 

 terior ambulacrum have no sucking disk and no 

 rosette plates, as is, otherwise, generally the 

 case; they are sack-shaped gills without spicules, 

 quite like the tubefeet of the paired petals. 

 There are no distinct subanal tubefeet. In the 

 tubefeet at the peristome some few irregular rods 

 or fenestrated plates are found below the disk; 

 the supporting rods of their filaments are simple, 

 not thickened. 



KOEHLER has found only one kind of pedi- 

 cellaria?, viz. the interesting two-valved form 

 figured in PI. II. Fig. 12 (Op. cit). I have like- 

 wise found this form, which evidently repre- 

 sents the tridentate pedicellariae, in great num- 

 bers and different sizes, from quite small to 

 0.8 length of head (PI. XIX Figs. 1—2, 6, 11, 

 22, 26) The valves are narrow, curved, the 

 blade being a closed tube, only with a short 

 slit downwards from the outer, slightly widened, 

 part, where the valves join; in the small ones the blade is open in the whole length. 

 There is no apophysis, a very interesting feature, not occurring in the bivalve pedi- 

 cellaria; of Abatns. The neck is well developed; the stalk is rather compact, without 

 distinct widening above; there is a more or less developed »milled rings below. — 

 Besides this form I have also found globiferous and rostrate pedicellaria?. Only one 

 specimen of globiferous pedicellariaj was found, and even a rather badly preserved 



Fig. 25. Actinal skeleton, left side, of 

 Amphipn. Lorioli. On the right side the 

 outline is somewhat uncertain in the part 



from the mark * to the posterior edge; the 

 same is the case with the hindmost right epi- 

 proctal plate and with the plates on the right 

 half of the peristome, these parts not having 

 been denuded. The plates on the periproct 

 were not drawn with camera. 



